Eighty-three patients with small cell lung cancer were randomized with or without using a traditional Chinese Kidney-tonifying decoction (Liu Wei Di Huang or Jin Gui Shen Qi medicinal decoction) in chemotherapy or radiotherapy courses. 74 patients were availble to be analysis. The two treatment groups were well-matched in age, sex, stage and performance status. There was a statistically significant difference in response rate and the median survival between two groups. The overall response rate (CR+PR) was 91.5% for Chinese herb group and 46.9% for control group (P less than 0.001). The median survival was 16 months for the traditional Chinese Kidney-tonifying decoction group, and 10 months for the control group (P less than 0.05). Survival curve (Kaplan-meire's) of the Chinese herb group was better than that of the control group. 10 patients of Chinese herb group was alive beyond more than 2 years. Until now, 4 patients in the Chinese herb group, one in the control group are still enjoying their disease-free life for more than 7 years. Hematologic toxicities were observed much frequently in the patients of the control group (P less than 0.005 and 0.01/WBC and BPC). Results of animal experiments with the same traditional medicinal decoctions as used in clinic have showed immuno-enhancement activities. These results have showed that the traditional Chinese Kidney-tonifying decoction may enhance non-specific immunology activities and may be much useful for solid cancer patients as an adjuvant treatment.