Cytotoxic agent remains the main chemotherapeutic drug for glioma, although it has many limitations. It is not known whether differentiation-inducing agent can enhance antitumor efficiency of cytotoxic agent. This study was designed to investigate anti-tumor effects of differentiation-inducing agent in combination with cytotoxic chemotherapeutic drug against glioma. Poorly-differentiated human brain glioma xenografted nude mice were treated with carmustine(1, 3-bis-(2-chloroethyl)-1-nitrosourea, BCNU) and sodium phenylbutyrate (SPB). The therapeutic effects were determined by measuring of tumor size, pathological changes, different phases of cell cycle of tumor cell proliferation, expression of differentiation antigen, and tumor cell apoptosis. The therapeutic effects of SPB plus BCNU group were much better than that of SPB or BCNU group alone, which were proved by lower growth rate of the tumor, cellularity decreasing, appearance of astroid-like polyglonal cells, G0/G1 ratio increasing, upregulation of GFAP expression. Combined application of SPB and BCNU can obviously inhibit proliferation of glioma, and promote differentiation of tumor cells.