Objective:To investigate the effects of synthetic retinoid CD437 and acitretin on cell proliferation,apoptosis,cycle arrest and Bax/Bcl-2 protein expression of melanoma A375 cell.Methods:MTT assay was used to determine the anti-proliferative effects of CD437 and acitretin on melanoma A375 cell.Flow cytometry was performed to investigate the influence of CD437 and acitretin on cell cycle and cell apoptosis.SABC immunocytochemistry was employed for detection of Bax/bcl-2 protein expressions.Results:10-5 mol/L CD437 was more effective than acitretin in inhibiting proliferation and inducing apoptosis of A375 cell after 24 h treatment,growth inhibiting ratio and apoptosis ratio(58.6%vs43.25% and 28.03%vs17.13%,P < 0.05 respectively).CD437 promoted G0/G1 arrest in melanoma A375 cell,however acitretin could not.CD437 and acitretin could up-regulate the expression of Bax protein and down-regulate the expression of bcl-2 protein(P < 0.05).Conclusion:CD437 is more effective than acitretin in inhibiting proliferation and inducing apoptosis and cycle arrest on A375 cell.CD437 may have more potentialities than acitretin for subsidiary treatment of melanoma.Mitochondrial apoptosis pathway is partially involved in two drugs inducing apoptosis on A375 cell. Objective: To investigate the effects of synthetic retinoid CD437 and acitretin on cell proliferation, apoptosis, cycle arrest and Bax / Bcl-2 protein expression of melanoma A375 cell. Methods: MTT assay was used to determine the anti-proliferative effects of CD437 and acitretin on melanoma A375 cell. Flow cytometry was performed to investigate the influence of CD437 and acitretin on cell cycle and cell apoptosis. SABC immunocytochemistry was employed for detection of Bax / bcl-2 protein expressions. Results: 10-5 mol / L CD437 was more effective than acitretin in inhibiting proliferation and inducing apoptosis of A375 cells after 24 h treatment, growth inhibition ratio and apoptosis ratio (58.6% vs 43.25% and 28.03% vs 17.13%, P <0.05 respectively) .CD437 promoted G0 / G1 arrest in melanoma A375 cell, however, acitretin could not.CD437 and acitretin could up-regulate the expression of Bax protein and down-regulate the expression of bcl-2 protein (P <0.05) .Conclusion: CD437 is more effective than acitretin in inh ibiting proliferation and inducing apoptosis and cycle arrest on A375 cell. CD437 may have more potentialities than acitretin for subsidiary treatment of melanoma. Mitochondrial apoptosis pathway is partially involved in two drugs inducing apoptosis on A375 cell.