Abstract: To investigate the physiological regulation of S-abscisic acid on maize under low temperature stress, the seeds of‘Dafeng 30’were used as the materials, and were coated with different concentrations of Sabscisic acid (0.2, 0.4, 0.6, 0.8, 1.0 mg/kg). After seed germination, the low temperature environment was simulated in the incubator. The physiological indexes, such as biological characteristics, root activity, chlorophyll content and leaf protective enzyme activity, were determined when the corns were at three leaves stage. The results showed that under low temperature stress, the growth, root activity, chlorophyll content and protective enzyme were significantly improved, while the content of peroxide malondialdehyde (MDA) in the membrane lipid was reduced. Meanwhile, the accumulations of reducing sugar and soluble protein were increased, and exhibited a tendency of first increasing and then reducing, with the increasing of S-abscisic acid. It indicates that the regulation of cold tolerance of corn has concentration effect to some extent, showing “Hormesis effect”.