Purpose: The effect of anti-cancer drug against brain tumor is not enough and glioma usually has a poor outcome.In this study, we focused attention on a thermoreversible gelation polymer (TGP, Mebiol(r) Gel) to localize the microspheres releasing an anti-cancer drug, such as camptothecin (CPT) and p53p-Ant in the brain.Methods: The anti-cancer effects after intracranial infusion of PLGA microspheres of these two types of anticancer drug dispersed in the TGP gel were determined in the rats bearing C6 glioma tumor.Results: The significant elongation of survival time in the rat glioma model was observed with these infusion systems by a single intracranial infusion compared with injection of the anti-cancer agent in solution or PLGA microspheres in PBS.Conclusion: These systems should be promising as a novel anti-cancer DDS for the brain tumor.The apoptosis and suppression of tumor growth by p53p-Ant has been confirmed in the C6 glioma cells.