Myelosupression is the major dose-limiting toxicity in most chemotherapeutic drugs. To evaluate the curative effect of a domestic product of rhG-CSF on chemotherapy-induced leukopenia, 132 patients with malignancies were enrolled, including 80 patients with lung cancer, 35 patients with breast cancer, 10 patients with nasopharyngeal carcinoma, 3 patients with non-Hodgkin's lymphoma, 2 patients with gastric carcinoma and 2 patients with bone metastasis. Total of 528 cycles of chemotherapy were performed. The results showed that according the grade of leukopenia, the different daily doses of the domestic product of rhG-CSF were administered: 75 micro g/d for 3 days, 150 micro g/d for 4 days and 300 micro g/d for 5 days, in grade I-II, grade III and grade IV groups, respectively, the times of recovery to normal level of white blood cells were 2.5, 4.2 and 7 days in 3 groups, respectively. In conclusion, The Chinese product of rhG-CSF shortened the duration of leukopenia and accelerated the hematologic recovery, which shows only slight side effects, so that patients receive the optimal doses of chemotherapy and completed the planned schedule on time.