diff --git a/crates/ruff_linter/src/codes.rs b/crates/ruff_linter/src/codes.rs
index 6b2a317bae..4449f06671 100644
--- a/crates/ruff_linter/src/codes.rs
+++ b/crates/ruff_linter/src/codes.rs
@@ -1184,6 +1184,16 @@ pub fn code_to_rule(linter: Linter, code: &str) -> Option<(RuleGroup, Rule)> {
         (Flake8Logging, "014") => (RuleGroup::Stable, rules::flake8_logging::rules::ExcInfoOutsideExceptHandler),
         (Flake8Logging, "015") => (RuleGroup::Stable, rules::flake8_logging::rules::RootLoggerCall),
 
+        // flake8-mock-spec
+        (Flake8MockSpec, "010") => (RuleGroup::Preview, rules::flake8_mock_spec::rules::Mock),
+        (Flake8MockSpec, "011") => (RuleGroup::Preview, rules::flake8_mock_spec::rules::MagicMock),
+        (Flake8MockSpec, "012") => (RuleGroup::Preview, rules::flake8_mock_spec::rules::NonCallableMock),
+        (Flake8MockSpec, "013") => (RuleGroup::Preview, rules::flake8_mock_spec::rules::AsyncMock),
+        (Flake8MockSpec, "014") => (RuleGroup::Preview, rules::flake8_mock_spec::rules::ThreadingMock),
+        (Flake8MockSpec, "020") => (RuleGroup::Preview, rules::flake8_mock_spec::rules::Patch),
+        (Flake8MockSpec, "021") => (RuleGroup::Preview, rules::flake8_mock_spec::rules::PatchObject),
+        (Flake8MockSpec, "022") => (RuleGroup::Preview, rules::flake8_mock_spec::rules::PatchMultiple),
+
         _ => return None,
     })
 }
diff --git a/crates/ruff_linter/src/registry.rs b/crates/ruff_linter/src/registry.rs
index 9351cb5de2..7566895f08 100644
--- a/crates/ruff_linter/src/registry.rs
+++ b/crates/ruff_linter/src/registry.rs
@@ -112,6 +112,9 @@ pub enum Linter {
     /// [flake8-logging-format](https://pypi.org/project/flake8-logging-format/)
     #[prefix = "G"]
     Flake8LoggingFormat,
+    /// [flake8-mock-spec](https://pypi.org/project/flake8-mock-spec/)
+    #[prefix = "TMS"]
+    Flake8MockSpec,
     /// [flake8-no-pep420](https://pypi.org/project/flake8-no-pep420/)
     #[prefix = "INP"]
     Flake8NoPep420,
diff --git a/crates/ruff_linter/src/rules/flake8_mock_spec/rules/async_mock.rs b/crates/ruff_linter/src/rules/flake8_mock_spec/rules/async_mock.rs
new file mode 100644
index 0000000000..6f1814a49f
--- /dev/null
+++ b/crates/ruff_linter/src/rules/flake8_mock_spec/rules/async_mock.rs
@@ -0,0 +1,33 @@
+use ruff_macros::{ViolationMetadata, derive_message_formats};
+
+use crate::Violation;
+
+#[derive(ViolationMetadata)]
+pub(crate) struct AsyncMock;
+
+impl Violation for AsyncMock {
+    #[derive_message_formats]
+    fn message(&self) -> String {
+        "`unittest.mock.AsyncMock` without `spec` or `spec_set` argument".to_string()
+    }
+}
+
+pub(crate) fn mock(checker: &Checker, call: &ast::ExprCall) {
+    if !checker.semantic().seen_module(Modules::UNITTEST) {
+        return;
+    }
+
+    if checker
+        .semantic()
+        .resolve_qualified_name(&call.func)
+        .is_some_and(|qualified_name| {
+            matches!(qualified_name.segments(), ["unittest", "mock", "AsyncMock"])
+        })
+    {
+        if call.arguments.find_argument("spec", 0).is_none()
+            && call.arguments.find_keyword("spec_set").is_none()
+        {
+            let mut diagnostic = checker.report_diagnostic(AsyncMock, call.func.range());
+        }
+    }
+}
diff --git a/crates/ruff_linter/src/rules/flake8_mock_spec/rules/magic_mock.rs b/crates/ruff_linter/src/rules/flake8_mock_spec/rules/magic_mock.rs
new file mode 100644
index 0000000000..efe788d2eb
--- /dev/null
+++ b/crates/ruff_linter/src/rules/flake8_mock_spec/rules/magic_mock.rs
@@ -0,0 +1,33 @@
+use ruff_macros::{ViolationMetadata, derive_message_formats};
+
+use crate::Violation;
+
+#[derive(ViolationMetadata)]
+pub(crate) struct MagicMock;
+
+impl Violation for MagicMock {
+    #[derive_message_formats]
+    fn message(&self) -> String {
+        "`unittest.mock.MagicMock` without `spec` or `spec_set` argument".to_string()
+    }
+}
+
+pub(crate) fn mock(checker: &Checker, call: &ast::ExprCall) {
+    if !checker.semantic().seen_module(Modules::UNITTEST) {
+        return;
+    }
+
+    if checker
+        .semantic()
+        .resolve_qualified_name(&call.func)
+        .is_some_and(|qualified_name| {
+            matches!(qualified_name.segments(), ["unittest", "mock", "MagicMock"])
+        })
+    {
+        if call.arguments.find_argument("spec", 0).is_none()
+            && call.arguments.find_keyword("spec_set").is_none()
+        {
+            let mut diagnostic = checker.report_diagnostic(MagicMock, call.func.range());
+        }
+    }
+}
diff --git a/crates/ruff_linter/src/rules/flake8_mock_spec/rules/mock.rs b/crates/ruff_linter/src/rules/flake8_mock_spec/rules/mock.rs
new file mode 100644
index 0000000000..a1d1bc95cc
--- /dev/null
+++ b/crates/ruff_linter/src/rules/flake8_mock_spec/rules/mock.rs
@@ -0,0 +1,33 @@
+use ruff_macros::{ViolationMetadata, derive_message_formats};
+
+use crate::Violation;
+
+#[derive(ViolationMetadata)]
+pub(crate) struct Mock;
+
+impl Violation for Mock {
+    #[derive_message_formats]
+    fn message(&self) -> String {
+        "`unittest.mock.Mock` without `spec` or `spec_set` argument".to_string()
+    }
+}
+
+pub(crate) fn mock(checker: &Checker, call: &ast::ExprCall) {
+    if !checker.semantic().seen_module(Modules::UNITTEST) {
+        return;
+    }
+
+    if checker
+        .semantic()
+        .resolve_qualified_name(&call.func)
+        .is_some_and(|qualified_name| {
+            matches!(qualified_name.segments(), ["unittest", "mock", "Mock"])
+        })
+    {
+        if call.arguments.find_argument("spec", 0).is_none()
+            && call.arguments.find_keyword("spec_set").is_none()
+        {
+            let mut diagnostic = checker.report_diagnostic(Mock, call.func.range());
+        }
+    }
+}
diff --git a/crates/ruff_linter/src/rules/flake8_mock_spec/rules/non_callable_mock.rs b/crates/ruff_linter/src/rules/flake8_mock_spec/rules/non_callable_mock.rs
new file mode 100644
index 0000000000..7676b7f412
--- /dev/null
+++ b/crates/ruff_linter/src/rules/flake8_mock_spec/rules/non_callable_mock.rs
@@ -0,0 +1,33 @@
+use ruff_macros::{ViolationMetadata, derive_message_formats};
+
+use crate::Violation;
+
+#[derive(ViolationMetadata)]
+pub(crate) struct NonCallableMock;
+
+impl Violation for NonCallableMock {
+    #[derive_message_formats]
+    fn message(&self) -> String {
+        "`unittest.mock.NonCallableMock` without `spec` or `spec_set` argument".to_string()
+    }
+}
+
+pub(crate) fn mock(checker: &Checker, call: &ast::ExprCall) {
+    if !checker.semantic().seen_module(Modules::UNITTEST) {
+        return;
+    }
+
+    if checker
+        .semantic()
+        .resolve_qualified_name(&call.func)
+        .is_some_and(|qualified_name| {
+            matches!(qualified_name.segments(), ["unittest", "mock", "NonCallableMock"])
+        })
+    {
+        if call.arguments.find_argument("spec", 0).is_none()
+            && call.arguments.find_keyword("spec_set").is_none()
+        {
+            let mut diagnostic = checker.report_diagnostic(NonCallableMock, call.func.range());
+        }
+    }
+}
diff --git a/crates/ruff_linter/src/rules/flake8_mock_spec/rules/patch.rs b/crates/ruff_linter/src/rules/flake8_mock_spec/rules/patch.rs
new file mode 100644
index 0000000000..493ce48f2a
--- /dev/null
+++ b/crates/ruff_linter/src/rules/flake8_mock_spec/rules/patch.rs
@@ -0,0 +1,36 @@
+use ruff_macros::{ViolationMetadata, derive_message_formats};
+
+use crate::Violation;
+
+#[derive(ViolationMetadata)]
+pub(crate) struct Patch;
+
+impl Violation for Patch {
+    #[derive_message_formats]
+    fn message(&self) -> String {
+        "`unittest.mock.patch` without one any `autospec`, `new`, `new_callable`, `spec` or `spec_set` argument".to_string()
+    }
+}
+
+pub(crate) fn mock(checker: &Checker, call: &ast::ExprCall) {
+    if !checker.semantic().seen_module(Modules::UNITTEST) {
+        return;
+    }
+
+    if checker
+        .semantic()
+        .resolve_qualified_name(&call.func)
+        .is_some_and(|qualified_name| {
+            matches!(qualified_name.segments(), ["unittest", "mock", "patch"])
+        })
+    {
+        if call.arguments.find_keyword("autospec").is_none()
+            && call.arguments.find_argument("new", 1).is_none()
+            && call.arguments.find_keyword("new_callable").is_none()
+            && call.arguments.find_keyword("spec").is_none()
+            && call.arguments.find_keyword("spec_set").is_none()
+        {
+            let mut diagnostic = checker.report_diagnostic(Patch, call.func.range());
+        }
+    }
+}
diff --git a/crates/ruff_linter/src/rules/flake8_mock_spec/rules/patch_multiple.rs b/crates/ruff_linter/src/rules/flake8_mock_spec/rules/patch_multiple.rs
new file mode 100644
index 0000000000..02f3860284
--- /dev/null
+++ b/crates/ruff_linter/src/rules/flake8_mock_spec/rules/patch_multiple.rs
@@ -0,0 +1,35 @@
+use ruff_macros::{ViolationMetadata, derive_message_formats};
+
+use crate::Violation;
+
+#[derive(ViolationMetadata)]
+pub(crate) struct PatchMultiple;
+
+impl Violation for PatchMultiple {
+    #[derive_message_formats]
+    fn message(&self) -> String {
+        "`unittest.mock.patch.multiple` without one any `autospec`, `new`, `new_callable`, `spec` or `spec_set` argument".to_string()
+    }
+}
+
+pub(crate) fn mock(checker: &Checker, call: &ast::ExprCall) {
+    if !checker.semantic().seen_module(Modules::UNITTEST) {
+        return;
+    }
+
+    if checker
+        .semantic()
+        .resolve_qualified_name(&call.func)
+        .is_some_and(|qualified_name| {
+            matches!(qualified_name.segments(), ["unittest", "mock", "patch", "multiple"])
+        })
+    {
+        if call.arguments.find_keyword("autospec").is_none()
+            && call.arguments.find_keyword("new_callable").is_none()
+            && call.arguments.find_argument("spec", 1).is_none()
+            && call.arguments.find_keyword("spec_set").is_none()
+        {
+            let mut diagnostic = checker.report_diagnostic(PatchMultiple, call.func.range());
+        }
+    }
+}
diff --git a/crates/ruff_linter/src/rules/flake8_mock_spec/rules/patch_object.rs b/crates/ruff_linter/src/rules/flake8_mock_spec/rules/patch_object.rs
new file mode 100644
index 0000000000..98ee8eaa29
--- /dev/null
+++ b/crates/ruff_linter/src/rules/flake8_mock_spec/rules/patch_object.rs
@@ -0,0 +1,36 @@
+use ruff_macros::{ViolationMetadata, derive_message_formats};
+
+use crate::Violation;
+
+#[derive(ViolationMetadata)]
+pub(crate) struct PatchObject;
+
+impl Violation for PatchObject {
+    #[derive_message_formats]
+    fn message(&self) -> String {
+        "`unittest.mock.patch.object` without one any `autospec`, `new`, `new_callable`, `spec` or `spec_set` argument".to_string()
+    }
+}
+
+pub(crate) fn mock(checker: &Checker, call: &ast::ExprCall) {
+    if !checker.semantic().seen_module(Modules::UNITTEST) {
+        return;
+    }
+
+    if checker
+        .semantic()
+        .resolve_qualified_name(&call.func)
+        .is_some_and(|qualified_name| {
+            matches!(qualified_name.segments(), ["unittest", "mock", "patch", "object"])
+        })
+    {
+        if call.arguments.find_keyword("autospec").is_none()
+            && call.arguments.find_argument("new", 2).is_none()
+            && call.arguments.find_keyword("new_callable").is_none()
+            && call.arguments.find_keyword("spec").is_none()
+            && call.arguments.find_keyword("spec_set").is_none()
+        {
+            let mut diagnostic = checker.report_diagnostic(PatchObject, call.func.range());
+        }
+    }
+}
diff --git a/crates/ruff_linter/src/rules/flake8_mock_spec/rules/threading_mock.rs b/crates/ruff_linter/src/rules/flake8_mock_spec/rules/threading_mock.rs
new file mode 100644
index 0000000000..f49bb8e734
--- /dev/null
+++ b/crates/ruff_linter/src/rules/flake8_mock_spec/rules/threading_mock.rs
@@ -0,0 +1,33 @@
+use ruff_macros::{ViolationMetadata, derive_message_formats};
+
+use crate::Violation;
+
+#[derive(ViolationMetadata)]
+pub(crate) struct ThreadingMock;
+
+impl Violation for ThreadingMock {
+    #[derive_message_formats]
+    fn message(&self) -> String {
+        "`unittest.mock.ThreadingMock` without `spec` or `spec_set` argument".to_string()
+    }
+}
+
+pub(crate) fn mock(checker: &Checker, call: &ast::ExprCall) {
+    if !checker.semantic().seen_module(Modules::UNITTEST) {
+        return;
+    }
+
+    if checker
+        .semantic()
+        .resolve_qualified_name(&call.func)
+        .is_some_and(|qualified_name| {
+            matches!(qualified_name.segments(), ["unittest", "mock", "ThreadingMock"])
+        })
+    {
+        if call.arguments.find_argument("spec", 0).is_none()
+            && call.arguments.find_keyword("spec_set").is_none()
+        {
+            let mut diagnostic = checker.report_diagnostic(ThreadingMock, call.func.range());
+        }
+    }
+}
diff --git a/crates/ruff_python_semantic/src/model.rs b/crates/ruff_python_semantic/src/model.rs
index 4f2dc47162..33ea4798c5 100644
--- a/crates/ruff_python_semantic/src/model.rs
+++ b/crates/ruff_python_semantic/src/model.rs
@@ -1485,6 +1485,7 @@ impl<'a> SemanticModel<'a> {
             "airflow" => self.seen.insert(Modules::AIRFLOW),
             "hashlib" => self.seen.insert(Modules::HASHLIB),
             "crypt" => self.seen.insert(Modules::CRYPT),
+            "unittest" => self.seen.insert(Modules::UNITTEST),
             _ => {}
         }
     }
@@ -2196,6 +2197,7 @@ bitflags! {
         const AIRFLOW = 1 << 27;
         const HASHLIB = 1 << 28;
         const CRYPT = 1 << 29;
+        const UNITTEST = 1 << 30;
     }
 }