Twenty-five courses (twenty-two pts) with NSCLC have been entered in the trial evaluating the combination of CDDP 20 mg/m2 i.v. day 1, 2, 3, 4, 5, CQ 7 mg/m2 i.v. day 1, and PS 30 mg/body per os day 1, 2, 3, 4, 5, repeated every 4 weeks. Except for 1 case of early death, judgement of efficacy was possible in 24 courses, including one case of squamous cell carcinoma and 23 cases of adenocarcinoma. CR was obtained in no cases and PR in 7 cases, all of which were adenocarcinoma, with an efficacy rate of 29%. Response for primary site was obtained in 4 of 22 cases (18%). Median survival time of the 22 cases was 11.5 months. Main side effects of PPQ Therapy were symptoms in digestive organs such as nausea and loss of appetite, and bone marrow inhibition. Renal dysfunction was controllable by measures to cope with diuresis.