diff --git a/requirements.txt b/requirements.txt
index 90e11d7..caeee57 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,5 +1,5 @@
 paho_mqtt
-cryptography
+cryptography>=3.1
 requests
 zeroconf
 attrs
diff --git a/setup.py b/setup.py
index 819b81b..e1d72dc 100644
--- a/setup.py
+++ b/setup.py
@@ -3,7 +3,7 @@
 
 REQUIRES = [
     "paho_mqtt",
-    "cryptography",
+    "cryptography>=3.1",
     "requests",
     "zeroconf",
     "attrs",