diff --git a/Misc/NEWS.d/next/Library/2024-06-08-09-45-31.gh-issue-120244.8o9Dzr.rst b/Misc/NEWS.d/next/Library/2024-06-08-09-45-31.gh-issue-120244.8o9Dzr.rst
new file mode 100644
index 00000000000000..d21532f22a1d38
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2024-06-08-09-45-31.gh-issue-120244.8o9Dzr.rst
@@ -0,0 +1 @@
+Fix memory leak in :func:`re.sub()` when the replacement string contains backreferences.
diff --git a/Modules/_sre/sre.c b/Modules/_sre/sre.c
index 0547390454a30e..8ef35d0658c703 100644
--- a/Modules/_sre/sre.c
+++ b/Modules/_sre/sre.c
@@ -1572,6 +1572,7 @@ _sre_template_impl(PyObject *module, PyObject *pattern, PyObject *template)
         }
         self->items[i].literal = Py_XNewRef(literal);
     }
+    PyObject_GC_Track(self);
     return (PyObject*) self;
 
 bad_template: