diff --git a/Doc/library/stdtypes.rst b/Doc/library/stdtypes.rst
index c0a3d0b3a2a49e..c8acde8b57dcdb 100644
--- a/Doc/library/stdtypes.rst
+++ b/Doc/library/stdtypes.rst
@@ -1768,7 +1768,7 @@ expression support in the :mod:`re` module).
       cases.
 
 
-.. method:: str.format_map(mapping)
+.. method:: str.format_map(mapping, /)
 
    Similar to ``str.format(**mapping)``, except that ``mapping`` is
    used directly and not copied to a :class:`dict`.  This is useful
diff --git a/Misc/NEWS.d/next/Core and Builtins/2024-05-25-13-51-48.gh-issue-111999.L0q1gh.rst b/Misc/NEWS.d/next/Core and Builtins/2024-05-25-13-51-48.gh-issue-111999.L0q1gh.rst
new file mode 100644
index 00000000000000..4b1ca6ca5b0765
--- /dev/null
+++ b/Misc/NEWS.d/next/Core and Builtins/2024-05-25-13-51-48.gh-issue-111999.L0q1gh.rst	
@@ -0,0 +1 @@
+Fix the signature of :meth:`str.format_map`.
diff --git a/Objects/unicodeobject.c b/Objects/unicodeobject.c
index afff37467caf32..048f9a814c30af 100644
--- a/Objects/unicodeobject.c
+++ b/Objects/unicodeobject.c
@@ -13490,7 +13490,7 @@ Return a formatted version of the string, using substitutions from args and kwar
 The substitutions are identified by braces ('{' and '}').");
 
 PyDoc_STRVAR(format_map__doc__,
-             "format_map($self, /, mapping)\n\
+             "format_map($self, mapping, /)\n\
 --\n\
 \n\
 Return a formatted version of the string, using substitutions from mapping.\n\