diff --git a/src/com/mirantis/mk/KaasUtils.groovy b/src/com/mirantis/mk/KaasUtils.groovy
index d56d496..ca6af41 100644
--- a/src/com/mirantis/mk/KaasUtils.groovy
+++ b/src/com/mirantis/mk/KaasUtils.groovy
@@ -157,8 +157,8 @@
 
        def ffMeta = ciSpec['siTestsFeatureFlags'].tokenize(',').collect { it.trim() }
        ffMeta.addAll(ciConfig['si-tests-feature-flags'])
-       ciSpec['siTestsFeatureFlags'] = ffMeta.join(',')
 
+       ciSpec['siTestsFeatureFlags'] = ffMeta.unique().join(',')
        common.infoMsg("SI tests custom feature flags: ${ciSpec['siTestsFeatureFlags']}")
    }