Aim Platinum based combination regimens are firstline treatment option in treatment of NSCLC but the clinical utility has been limited because of their toxicities.Many reports indicated that patients with tumors can benefit from adjuvant chemotherapy drugs.The aim of this study was to confirm adjuvant chemotherapy of active protein P23 with docetaxel plus cisplatin (DP) against nonsmall cell lung cancer (NSCLC) by evaluating synergistic antitumor activity and attenuated effect.Methods In vivo SPCA1 xenograft model was established to evaluate antitumor activity and toxicity of P23 along or combination with DP.Evaluation indexes include the relative tumor proliferation rate, tumor growth inhibition rate, body weight, food consumption, hematological and biochemical analysis.Results P23 treatment showed inhibited tumor growth and increased tumor inhibition of DP treatment.No significant toxicity was found in P23treated mice, but significant toxicity was found in DPtreated mice.P23 combination with DP could reduce toxicity of DP treatment by improving body weight and food consumption, and increasing the number of WBC and PLT, decreasing the level of ALT, AST and BUN.Conclusion P23 combined with DP treatment has additive effect which contributes to enhance tumor growth inhibition of DP treatment and attenuated effect which contributes to reduce toxicity of DP treatment.These findings indicate potential benefit for use of P23 adjuvant chemotherapy for NSCLC treatment.