We evaluated the effect of aranulocyte colony stimulating factor (G-CSF) to prevent chemo- therapy induced neutropenia and fever development during neutropenic period. The twenty patients with solid tumor were treated with various cytotoxic chemotherapeutic agents at least two cycles. The patients were given G-CSF 75pg/day after 2nd cycle chemotherapy for least 14 consecutive days and clinical, laboratory results were compared to the first cycle's results. Treatment with G-CSF resulted in increase of mean neutrophil count(320+-230/mm(3) vs 1030 +-1020/mm(2)), reduced the duration of neutropenic days(4.25 dyas vs 1.30 days, absolute neutrophil count less than 500/mm) snd reduced the incidence of neutropenic fever(75% vs 25% ). The side effect af G-CSF was not so significant. These results demonsrated that the use of G-CSF as an adjunct to chemotherapy with various solid cancer patients was well tolerated and led to reduction in the incidence of neutropenic fever; in the terms of incidence, duratian, and severity of neutropenia.