Objective: To investigate the effect of Luteolin alone or combination with chemotherapentic drugs on the cytoxicity of cancer cells.Methods: Cultured A549,Hela,MCF-7,AGS,MGC-803,Caco2 and HepG2 cells were treated with Luteolin or the combination of Luteolin with other chemotherapeutic agents (Bexarotene,Cisplatin and Bleomycin).Cell viability was measured by MTS assay and IC_(50) was calculated.Results: The IC_(50) of Bexarotene to Hela cells was 2 μmol/L,but with the combination of 5 μmol/L of Luteolin that reduced to 0.2 μmol/L.However,the combination of Bexarotene and Luteolin did not show significant benefit in MGC-803,HepG2 cells,Caco2 and MCF-7 cells.The IC_(50) of Cisplatin to Hela cells was over 30 μmol/L,but it decreased to 3 μmol/L in the presence of 5 μmol/L Luteolin; Luteolin also sensitized Cisplatin in MGC-803,HepG2 and A549 cells studied.The IC_(50) of Bleomycin to Hela cells was over 100 μmol/L,but it was about 1 μmol/L in the presence of 5 μmol/L Luteolin.A549 cells were resistant to Bleomycin with an IC_(50) of 100 μmol/L,10 μmol/L Luteolin greatly enhanced the cytotoxicity of Bleomycin to the cells with the IC_(50) of about 10 μmol/L.The inhibitions of MGC-803,HepG2,A549 and AGS cells didn't change by combination of Luteolin.Conclusion: Low concentration of Luteolin has little toxic effect on the cancer cell lines tested in the study,but it can sensitize chemotherapeutic drugs in various cancer cell lines.