This study was purposed to explore the expression of P27(kip1)and cyclin G in patients with acute leukemia (AL) and its correlation. The reverse polymerase chain reaction (RT-PCR) was used to analyse the expression of P27(kip1) and cyclin G mRNA in 89 AL patients and 10 normal persons; Western blot was used to analyze the expression of P27(kip1) and cyclin G protein in 39 AL patients and 10 normal persons. The results showed that the cyclin G mRNA and protein expressions in new diagnosed/relapsed cases of AL were significantly higher than those in patients with remission and normal controls (p < 0.05 and p < 0.01), but there was no difference between remission cases and normal controls (p > 0.05). The expression of P27(kip1) mRNA in newly diagnosed/relapsed patients with AL was not significantly different from patients with remission and normal controls (p > 0.05), while the P27(kip1) protein expression in remission cases of AL and normal controls was significantly higher than that in new diagnosed/relapsed cases (p < 0.05), but there was no difference between remission cases and normal controls (p > 0.05). The expression of P27(kip1) negatively and lowly correlated with the expression of cyclin G in patients with AL. It is concluded that the low expression of P27(kip1) and the high expression of cyclin G in patients with AL may have some correlation with genesis and development of AL and may be an indication for poor prognosis of AL.