Abstract: In this paper, 5 maize cultivars were tested in different low frosting temperature. Measurement and analysis for the parameters such as photosynthesis rate, electrical conductivity (EC) and proline content were made to estimate the response of crop resistance to low temperatures. It was concluded that: more frost-resisting cultivars may be selected out in seeding stage by parameter measurement with smaller decrease both in photosynthetic rate and electrical conductivity and with the bigger increase in proline content. Among the five tested cultivars, the order of frost resistance from higher to lower was Shendan No.10, Zhongdan No.306, Nongda No.108, Jindan No32 and Shandan No.902.