diff --git a/requirements.txt b/requirements.txt
index 1df5b22..0f90a72 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -89,7 +89,7 @@ toolz==0.10.0
 tornado==6.0.3
 traitlets==4.3.3
 typed-ast==1.4.0
-ujson==1.35
+ujson==5.4.0
 urllib3==1.25.7
 wcwidth==0.1.7
 webencodings==0.5.1