diff --git a/stdlib/math/__init__.pyi b/stdlib/math/__init__.pyi
index 4839bf7e90df..b11324c4ae9a 100644
--- a/stdlib/math/__init__.pyi
+++ b/stdlib/math/__init__.pyi
@@ -90,7 +90,7 @@ def isqrt(n: SupportsIndex, /) -> int: ...
 def lcm(*integers: SupportsIndex) -> int: ...
 def ldexp(x: _SupportsFloatOrIndex, i: int, /) -> float: ...
 def lgamma(x: _SupportsFloatOrIndex, /) -> float: ...
-def log(x: _SupportsFloatOrIndex, base: _SupportsFloatOrIndex = ...) -> float: ...
+def log(x: _SupportsFloatOrIndex, base: _SupportsFloatOrIndex = ..., /) -> float: ...
 def log10(x: _SupportsFloatOrIndex, /) -> float: ...
 def log1p(x: _SupportsFloatOrIndex, /) -> float: ...
 def log2(x: _SupportsFloatOrIndex, /) -> float: ...