diff --git a/Misc/NEWS.d/next/Core and Builtins/2020-04-04-12-43-19.bpo-40077.m15TTX.rst b/Misc/NEWS.d/next/Core and Builtins/2020-04-04-12-43-19.bpo-40077.m15TTX.rst
new file mode 100644
index 00000000000000..21ed615917c59a
--- /dev/null
+++ b/Misc/NEWS.d/next/Core and Builtins/2020-04-04-12-43-19.bpo-40077.m15TTX.rst	
@@ -0,0 +1 @@
+Fix possible refleaks in :mod:`_json`, memo of PyScannerObject should be traversed.
diff --git a/Modules/_json.c b/Modules/_json.c
index 4682cf84621ee9..8117d1601bd3f8 100644
--- a/Modules/_json.c
+++ b/Modules/_json.c
@@ -652,6 +652,7 @@ scanner_traverse(PyScannerObject *self, visitproc visit, void *arg)
     Py_VISIT(self->parse_float);
     Py_VISIT(self->parse_int);
     Py_VISIT(self->parse_constant);
+    Py_VISIT(self->memo);
     return 0;
 }