Abstract: Objective 　To study the effect and mechanism of ATRA on the survival time of Wistar rat with int racerebral C6 glioma. Methods 　By establishing rat C6 glioma brain tumor model, tumor2bearing rat s were divided into the cont rol group and the ATRA t reatment group on the seventh day after implanta2 tion. The expression of the p27kip1 protein was detected on the 22nd day following inoculation and sur2 vival time of the rat s was observed. Results 　The expression of the p27kip1 protein was increased and survival time of the rat s was prolonged in the t reatment group as compared with that of the cont rol group ( P < 0. 05) . There was a positive correlation between the expression of the p27kip1 protein and survival. Conclusion 　ATRA can prolong the survival time of tumor2bearing rat s, it s mechanism is concerned with the upregulation of p27kip1 protein. the p27kip1 protein expression can be used as a marker to predict the prognosis of glioma.