With the aim of evaluating the safety and efficacy of filgrastim biosimilar 1(Filgrastim BS syringe for Inj. "MOCHIDA"and "F"), we conducted a drug use results survey of this product for its indications, including mobilization of hematopoietic stem cells into peripheral blood and chemotherapy-induced neutropenia. Of the 518 cases enrolled between August 2013 and July 2015, 495 were selected to be subjects of our safety and efficacy evaluations. 37 cases (7.47%)experienced side effects, which were mainly lower back pain(19, 3.84%), fever(8, 1.62%)and bone pain(3, 0.61%). As for serious side effects, interstitial pneumonia was reported in 2 cases, but this disorder has already been ecognized as being associated with the use of filgrastim originator, and there were no reports of unknown side effects calling for immediate attention. In addition, we investigated hypersensitivity reactions(such as nettle rash and anaphylactic shock)and diminished drug effects, both of which are considered to be attributable to immunogenicity, and found that non-serious nettle rash was reported in 2 cases. However, there have been no reports of anaphylactic shock or diminished drug effects. The efficacy rate based on physicians' clinical observations was 97.98%. This study confirmed that there are no problems with the clinical use of filgrastim biosimilar 1.