diff --git a/navalplanner-business/src/main/java/org/navalplanner/business/orders/entities/OrderElement.java b/navalplanner-business/src/main/java/org/navalplanner/business/orders/entities/OrderElement.java
index 3c76b424e..8b20ffc06 100644
--- a/navalplanner-business/src/main/java/org/navalplanner/business/orders/entities/OrderElement.java
+++ b/navalplanner-business/src/main/java/org/navalplanner/business/orders/entities/OrderElement.java
@@ -31,8 +31,8 @@ import java.util.HashMap;
 import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
-import java.util.Map.Entry;
 import java.util.Set;
+import java.util.Map.Entry;
 
 import org.apache.commons.lang.Validate;
 import org.hibernate.validator.AssertTrue;
@@ -1362,4 +1362,17 @@ public abstract class OrderElement extends IntegrationEntity implements
         return getOrder() != null ? getOrder().isCodeAutogenerated() : false;
     }
 
+    @AssertTrue(message = "a quality form can not be assigned twice to the same order element")
+    public boolean checkConstraintUniqueQualityForm() {
+        Set<QualityForm> qualityForms = new HashSet<QualityForm>();
+        for (TaskQualityForm each : taskQualityForms) {
+            QualityForm qualityForm = each.getQualityForm();
+            if (qualityForms.contains(qualityForm)) {
+                return false;
+            }
+            qualityForms.add(qualityForm);
+        }
+        return true;
+    }
+
 }