diff --git a/time_operator/requirements.txt b/time_operator/requirements.txt
index 6b85f78..53f3764 100644
--- a/time_operator/requirements.txt
+++ b/time_operator/requirements.txt
@@ -1,3 +1,3 @@
 # Dependencies
-ujson==2.0.3
+ujson==5.4.0
 numpy==1.18.2