Docetaxel has been the only single active agent against chemotherapy-pretreated non-small-cell lung cancer (NSCLC). The purpose of this phase 11 study was to evaluate the efficacy and safety of docetaxel combined with gemcitabine, another effective drug, in patients with NSCLC previously treated with platinum-based chemotherapy. Thirty-three patients were enrolled. Prior chemotherapy was cisplatin combined with etoposide in 24 patients and vinorelbine in 9 patients. Tumors were sensitive (n = 15), resistant (n = 9), and refractory (n = 9) to front-line chemotherapy. Treatment was docetaxel 85 mg/m(2) on d 1, and gemcitabine 1200 mg/m(2) on d 1 and 8, with cycles repeated every three weeks. Ten patients (30.3%, 95% CI: 15.6-48.7) achieved a partial response and 15 (45.5%) stable disease. Responses were similar frequencies in platinum-sensitive and platinum-resistant/refractory tumors. With a median follow-up period of 5.7 mo (range 1.6-20.0), the median and 6-mo event-free survival were 5.5 mo, 40.6%, respectively. Median and 6-mo overall survival were 7.3 mo and 52.7%. Patients with progressive disease to chemotherapy (p = 0.0008), higher LDH (p = 0.005), and NSE levels (p = 0.03) survived shorter than other patients. In patients refractory to prior chemotherapy, survival was poor as borderline significantly (p = 0.06). The major hematological toxicity was neutropenia. Grade III-IV neutropenia was noted in 14 (42%) patients, with three episodes of febrile neutropenia in I I I cycles. Docetaxel combined with gemcitabine is an active and safe second-line therapy for patients with NSCLC.