Even though air compressors for traditional vehicles and fuel cell vehicles (FCVs) share many similarities, a fuel cell vehicle cannot directly employ the effective and mass-produced traditional vehicles' air compressors. This is because the fuel cell vehicles have special requirements, such as oil free, low flow rate with high pressure ratio, high efficiency, and low weight and volume.In order to find suitable air compressors to match the fuel cell system (FCS)'s requirements, different air compressors' performance and physical characteristics are compared. These air compressors include screw compressor with expander, roots compressor with expander, turbocompressor, and scroll compressor with expander. The comparison and analysis is both theoretical and practical.Results show that the turbocompressor and the roots compressor/expander have higher performance compared to the others in the aspects of input power, system efficiency, weight, and volume. However, the two of them also show some defects. The turbocompressor has a limited turndown ratio due to the surge. And the roots compressor has a limited pressure ratio and pulsation characteristics.The application of air compressors in FCVs is also studied. Literature review indicates that the turbocompressor is most popular among all FCVs. All the findings in this research will contribute to the selection and design of the air compressors for FCVs, which are on the edge of mass production.