diff --git a/postgres/tasks/main.yml b/postgres/tasks/main.yml
index 60b17952028be77ea45c0338993cf6951468ddb8..725f9edc3e34e06bb4e32d0c95bf90e196136263 100644
--- a/postgres/tasks/main.yml
+++ b/postgres/tasks/main.yml
@@ -24,7 +24,7 @@
       - libpq-dev
     state: present
 
-- when: not postgres_version is defined
+- when: postgres_version is not defined
   block:
     - name: Check installed software
       package_facts: