Experiments about engine performance using alcohol-gasoline blend as a fuel are studied. A conventional 4cycle 4cylinder gasoline engine is used. Measurements on torque, output, specific fuel consumption, and emissions are made over ignition timing and mixing ratio. Up to vol. 15% of alcohol, torque and output using alcohol-gasoline blend are almost same with using only gasoline, and specific fuel consumption is improved about 7%. In emissions alcohol-gasoline blend is more effective than gasoline.