diff --git a/apis/keda/v1alpha1/scaledobject_types.go b/apis/keda/v1alpha1/scaledobject_types.go
index eac00b52496..e35ec931fc8 100644
--- a/apis/keda/v1alpha1/scaledobject_types.go
+++ b/apis/keda/v1alpha1/scaledobject_types.go
@@ -112,6 +112,7 @@ type Fallback struct {
 	FailureThreshold int32 `json:"failureThreshold"`
 	Replicas         int32 `json:"replicas"`
 	// +optional
+	// +kubebuilder:validation:Enum=static;useCurrentReplicasAsMinimum
 	Behavior string `json:"behavior,omitempty"`
 }