diff --git a/Core/MIPS/MIPSDebugInterface.h b/Core/MIPS/MIPSDebugInterface.h
index 26ee3e9d6f..8014720bb4 100644
--- a/Core/MIPS/MIPSDebugInterface.h
+++ b/Core/MIPS/MIPSDebugInterface.h
@@ -121,7 +121,8 @@ public:
 		switch (cat)
 		{
 		case 0:
-			cpu->r[index] = value;
+			if (index != 0)
+				cpu->r[index] = value;
 			break;
 
 		case 1: