RT-PCR is applied to observe the effects of excessive and deficient Zn2+ on the expression of wild type-p53 (wt-p53) in rat glicoma cells. Rat glicoma cells in garithmic growth phase is treated with 0.3 mmol/L Zn2+ and 5 mumol/L TPEN respectively for 24 hours. Results show that the expression of wt-p53 of rat glicoma cells increased obviously in the deficient zinc group but does not increased in the excessive zinc group. These indicate that the expression of wt-p53 mRNA of rat glicoma cells is up-regulated by deficient zinc and inhibited by excessive zinc.