diff --git a/src/main/java/de/hs_mannheim/domain/System.java b/src/main/java/de/hs_mannheim/domain/System.java
index 02f4dd0..476a481 100644
--- a/src/main/java/de/hs_mannheim/domain/System.java
+++ b/src/main/java/de/hs_mannheim/domain/System.java
@@ -111,7 +111,7 @@ public class System {
         return false;
     }
 
-    public boolean sign_up_user(String username, String password, String hometown, String zip,
+    public boolean sign_up_user(String username, String password, String password_authentication, String hometown, String zip,
                                 String car_name, String car_l_100kmS, String car_avg_kmhS, String bike_avg_kmhS){
 
         double car_l_100km;
@@ -129,6 +129,9 @@ public class System {
         if(username.equals("")||password.equals("")||hometown.equals("")||zip.equals(""))
             return false;
 
+        if(!password.equals(password_authentication))
+            return false;
+
         for(User user: this.all_user)
             if(user.getUsername().equals(username))
                 return false;
diff --git a/src/main/java/de/hs_mannheim/facade/Application.java b/src/main/java/de/hs_mannheim/facade/Application.java
index 015597b..d771bde 100644
--- a/src/main/java/de/hs_mannheim/facade/Application.java
+++ b/src/main/java/de/hs_mannheim/facade/Application.java
@@ -16,9 +16,9 @@ public class Application {
         return running_system.sign_in_user(username, password);
     }
 
-    public boolean sign_up_user(String username, String password, String hometown, String zip,
+    public boolean sign_up_user(String username, String password, String password_authentication, String hometown, String zip,
                                 String car_name, String car_co2_km, String car_avg_kmh, String bike_avg_kmh){
-        return running_system.sign_up_user(username, password, hometown, zip, car_name, car_co2_km, car_avg_kmh, bike_avg_kmh);
+        return running_system.sign_up_user(username, password, password_authentication, hometown, zip, car_name, car_co2_km, car_avg_kmh, bike_avg_kmh);
     }
 
     public void sign_out_user(){
diff --git a/src/test/java/de/hs_mannheim/domain/SystemTest.java b/src/test/java/de/hs_mannheim/domain/SystemTest.java
index 24344b0..31fe19a 100644
--- a/src/test/java/de/hs_mannheim/domain/SystemTest.java
+++ b/src/test/java/de/hs_mannheim/domain/SystemTest.java
@@ -123,11 +123,11 @@ public class SystemTest {
     @Test
     public void sign_up_user(){
         // Username darf nicht doppelt vorkommen!
-        assertEquals(false, current_system.sign_up_user("David","123Esel","Mannheim","68161","AMG","10","300","20"));
-        assertEquals(true, current_system.sign_up_user("Selim","Penis69","Mannheim","68161","AMG","10","300","20"));
+        assertEquals(false, current_system.sign_up_user("David","123Esel","123Esel","Mannheim","68161","AMG","10","300","20"));
+        assertEquals(true, current_system.sign_up_user("Selim","Penis69","Penis69","Mannheim","68161","AMG","10","300","20"));
         // PLZ muss mit Stadt übereinstimmen
-        assertEquals(false, current_system.sign_up_user("Lukas","123Esel","Mannheim","11105","AMG","10","300","20"));
-        assertEquals(true, current_system.sign_up_user("Lukas","123Esel","Mannheim","68305","AMG","10","300","20"));
+        assertEquals(false, current_system.sign_up_user("Lukas","123Esel","123Esel","Mannheim","11105","AMG","10","300","20"));
+        assertEquals(true, current_system.sign_up_user("Lukas","123Esel","123Esel","Mannheim","68305","AMG","10","300","20"));
 
         assertEquals("Lukas",current_system.getDetails()[0]);
         current_system.sign_out_user();