To face the challenges of fossil fuel shortage and air pollution problems, there is growing interest in the potential usage of alternative fuels such as bio-ethanol and bio-butanol in internal combustion engines. The literature shows that the acetone in the Acetone-Butanol-Ethanol (ABE) blends plays an important part in improving the combustion performance and emissions, owing to its higher volatility. In order to study the effects of acetone addition into commercial gasoline, this study focuses on the differences in combustion, performance and emission characteristics of a port-injection spark-ignition engine fueled with pure gasoline (G100), ethanol-containing gasoline (E30) and acetone-ethanol-gasoline blends (AE30 at A:E volumetric ratio of 3:1). The tests were conducted at 1200RPM with the default calibration (for gasoline), at 3 bar and 5 bar BMEP under various equivalence ratios. The combustion characteristics, brake thermal efficiency, brake specific fuel consumption and various emissions of different fuels were compared, respectively. Results showed there was a slight increase in BTE and improved BSFC with AE30 relative to E30. It was also found that AE30 showed lower HC emissions because of the better volatility of the acetone additive. Although the CO emission was a bit higher at stoichiometric conditions, it might reduce at fuel-rich conditions such as full load and transient accelerating. No obvious differences of NOx emissions were invested between the tested fuels.