diff --git a/libreplan-business/src/main/java/org/libreplan/business/expensesheet/entities/ExpenseSheet.java b/libreplan-business/src/main/java/org/libreplan/business/expensesheet/entities/ExpenseSheet.java
index 88c6d6b53..6728e7b74 100644
--- a/libreplan-business/src/main/java/org/libreplan/business/expensesheet/entities/ExpenseSheet.java
+++ b/libreplan-business/src/main/java/org/libreplan/business/expensesheet/entities/ExpenseSheet.java
@@ -232,4 +232,13 @@ public class ExpenseSheet extends IntegrationEntity implements IHumanIdentifiabl
         return !personal;
     }
 
+    @AssertTrue(message = "a personal expenses must have at least one line")
+    public boolean checkConstraintPersonalExpenseMustHaveAtLeastOneLine() {
+        if (!personal) {
+            return true;
+        }
+
+        return !expenseSheetLines.isEmpty();
+    }
+
 }
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