Abstract: The survival rate,GR activity and the content of heat stable protein and proline of maize seedlings were surveyed after the seeds were soaked with CaCl2 solution and/or the seedlings were shocked with heat prior to chilling treatment.It was found these parameters of the heat shocked seedlings were higher than that of contrast,and the highest ones of them were is that of seedlings which were treated by heat shock associated with CaCl2 solution.So it is suggested heat shock pretreatment can raise the resistance of plants to chilling, and Ca2+ can strengthen this function of heat shock.