diff --git a/app/src/main/java/org/ntlab/irisclient/OwnerRoomActivity.java b/app/src/main/java/org/ntlab/irisclient/OwnerRoomActivity.java
index fb9712b..2138508 100644
--- a/app/src/main/java/org/ntlab/irisclient/OwnerRoomActivity.java
+++ b/app/src/main/java/org/ntlab/irisclient/OwnerRoomActivity.java
@@ -48,6 +48,10 @@
     ArrayList<String> viewMembers = new ArrayList<>();
     ArrayList<String> oldMembers = new ArrayList<>();
     List<Member> allMembers = new ArrayList<>();
+    List<Integer> Mteam = new ArrayList<>();
+    List<Integer> Steam = new ArrayList<>();
+    List<Integer> Rteam = new ArrayList<>();
+    List<Integer> Bteam = new ArrayList<>();
     String roomId = "null";
     String myName = "null";
     //String nickname;
@@ -228,10 +232,14 @@
         startButton.setOnClickListener(new View.OnClickListener() {
             @Override
             public void onClick(View v) {
-                roomViewModel.startDrawing(roomId, myName);
+                if(ConditionStart()){
+                    roomViewModel.startDrawing(roomId, myName);
 
-                Intent intent = new Intent(OwnerRoomActivity.this,DrawingActivity.class);
-                startActivity(intent);
+                    Intent intent = new Intent(OwnerRoomActivity.this,DrawingActivity.class);
+                    startActivity(intent);
+                }else{
+                    Snackbar.make(v, "スタート条件を満たしていません", Snackbar.LENGTH_LONG).show();
+                }
 
             }
         });
@@ -309,4 +317,36 @@
         }
     }
 
+    public boolean ConditionStart() {
+        for(int i=0; i< allMembers.size(); i++){
+
+            if(allMembers.get(i).getMaster()){
+                Mteam.add(i);
+            }else{
+                Steam.add(i);
+            }
+
+            if(allMembers.get(i).getBelongs().equals("r")){
+                Rteam.add(i);
+            }else if(allMembers.get(i).getBelongs().equals("b")) {
+                Bteam.add(i);
+            }
+
+        }
+
+        if(Mteam.size() != 2){
+            return false;
+        }
+
+        if(Rteam.size() < 2){
+            return false;
+        }
+
+        if(Bteam.size() < 2){
+            return false;
+        }
+
+        return true;
+    }
+
 }
\ No newline at end of file