The effect of CDDP + VDS has been evaluated in 39 cases of non-small cell lung cancer, compared with those treated with radiation alone. Nineteen cases consisted of a combined radiation and chemotherapy group, while twenty cases were classed a the radiation therapy only group. CDDP was given at a dosage of 60 to 110 mg/m2 every 4 weeks, and VDS at a dosage of 3 mg/m2 3 times weekly. Radiation was given at a fraction dose of 1.5 to 2 Gy 5 times per week with a mean total dose of 56 Gy in the radiation only group, and 50 Gy in the combined therapy group. There were no significant difference in both the response rate and the survival time between the two groups. This suggests that combined chemotherapy was not effective for the treatment of non-small cell lung cancer.