diff --git a/Lib9c/Helper/AdventureBossHelper.cs b/Lib9c/Helper/AdventureBossHelper.cs
index c8eed37776..941d08de25 100644
--- a/Lib9c/Helper/AdventureBossHelper.cs
+++ b/Lib9c/Helper/AdventureBossHelper.cs
@@ -1,7 +1,6 @@
 using System;
 using System.Collections.Generic;
 using System.Collections.Immutable;
-using System.Globalization;
 using System.Linq;
 using Nekoyume.Module;
 using Lib9c;
@@ -283,8 +282,9 @@ public static AdventureBossGameData.ClaimableReward CalculateExploreReward(
 
             // calculate ncg reward
             var totalNcgReward = (bountyBoard.totalBounty() * 15).DivRem(100, out _);
-            var myNcgReward = (totalNcgReward * explorer.Score)
-                .DivRem(exploreBoard.TotalPoint, out _);
+            var myNcgReward = exploreBoard.TotalPoint == 0
+                ? 0 * totalNcgReward.Currency
+                : (totalNcgReward * explorer.Score).DivRem(exploreBoard.TotalPoint, out _);
 
             // Only > 0.1 NCG will be rewarded.
             if (myNcgReward >= (10 * gold).DivRem(100, out _))