diff --git a/sample-macruby/Suru/Suru.xcodeproj/project.pbxproj b/sample-macruby/Suru/Suru.xcodeproj/project.pbxproj
index 2fc0d94fc..67078f6af 100755
--- a/sample-macruby/Suru/Suru.xcodeproj/project.pbxproj
+++ b/sample-macruby/Suru/Suru.xcodeproj/project.pbxproj
@@ -260,7 +260,6 @@
 				GCC_WARN_ABOUT_RETURN_TYPE = YES;
 				GCC_WARN_UNUSED_VARIABLE = YES;
 				PREBINDING = NO;
-				SDKROOT = "$(DEVELOPER_SDK_DIR)/MacOSX10.5.sdk";
 			};
 			name = Debug;
 		};
@@ -272,7 +271,6 @@
 				GCC_WARN_ABOUT_RETURN_TYPE = YES;
 				GCC_WARN_UNUSED_VARIABLE = YES;
 				PREBINDING = NO;
-				SDKROOT = "$(DEVELOPER_SDK_DIR)/MacOSX10.5.sdk";
 			};
 			name = Release;
 		};