diff --git a/crates/ruff_linter/resources/test/fixtures/flake8_bugbear/B009_B010.py b/crates/ruff_linter/resources/test/fixtures/flake8_bugbear/B009_B010.py
index c47538b55e..ce6e5c291e 100644
--- a/crates/ruff_linter/resources/test/fixtures/flake8_bugbear/B009_B010.py
+++ b/crates/ruff_linter/resources/test/fixtures/flake8_bugbear/B009_B010.py
@@ -67,3 +67,6 @@ getattr(self.
 
 import builtins
 builtins.getattr(foo, "bar")
+
+# Regression test for: https://github.com/astral-sh/ruff/issues/18353
+setattr(foo, "__debug__", 0)
diff --git a/crates/ruff_linter/src/rules/flake8_bugbear/rules/setattr_with_constant.rs b/crates/ruff_linter/src/rules/flake8_bugbear/rules/setattr_with_constant.rs
index cfc2557341..a83710800d 100644
--- a/crates/ruff_linter/src/rules/flake8_bugbear/rules/setattr_with_constant.rs
+++ b/crates/ruff_linter/src/rules/flake8_bugbear/rules/setattr_with_constant.rs
@@ -74,6 +74,11 @@ pub(crate) fn setattr_with_constant(checker: &Checker, expr: &Expr, func: &Expr,
     if !is_identifier(name.to_str()) {
         return;
     }
+    // Ignore if the attribute name is `__debug__`. Assigning to the `__debug__` property is a
+    // `SyntaxError`.
+    if name.to_str() == "__debug__" {
+        return;
+    }
     if is_mangled_private(name.to_str()) {
         return;
     }
diff --git a/crates/ruff_linter/src/rules/flake8_bugbear/snapshots/ruff_linter__rules__flake8_bugbear__tests__B009_B009_B010.py.snap b/crates/ruff_linter/src/rules/flake8_bugbear/snapshots/ruff_linter__rules__flake8_bugbear__tests__B009_B009_B010.py.snap
index 5748ea4eb7..8bddcba720 100644
--- a/crates/ruff_linter/src/rules/flake8_bugbear/snapshots/ruff_linter__rules__flake8_bugbear__tests__B009_B009_B010.py.snap
+++ b/crates/ruff_linter/src/rules/flake8_bugbear/snapshots/ruff_linter__rules__flake8_bugbear__tests__B009_B009_B010.py.snap
@@ -364,6 +364,8 @@ B009_B010.py:69:1: B009 [*] Do not call `getattr` with a constant attribute valu
 68 | import builtins
 69 | builtins.getattr(foo, "bar")
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ B009
+70 |
+71 | # Regression test for: https://github.com/astral-sh/ruff/issues/18353
    |
    = help: Replace `getattr` with attribute access
 
@@ -373,3 +375,6 @@ B009_B010.py:69:1: B009 [*] Do not call `getattr` with a constant attribute valu
 68 68 | import builtins
 69    |-builtins.getattr(foo, "bar")
    69 |+foo.bar
+70 70 | 
+71 71 | # Regression test for: https://github.com/astral-sh/ruff/issues/18353
+72 72 | setattr(foo, "__debug__", 0)