The acute and subacute toxicity of New Wonbangwoohwangchungsimwon (NSCH) which was used l-muscone as substitutive material of musk were investigated in S.D. rats. In intraperitoneal acute toxicity test, rats were injected intraperitoneally with five dosages of 0, 500, 710, 1,000, 1,410 and 2,000 mg/kg. Body weights were significantly decreased at 500 and 710 mg/kg dose group in male and abnormal autopsy findings were founded in both sexes at all dose. Intraperitoneal $LD_{50}$ of NSCH was 1,088.3 mg/kg in male and 1159.3 mg/kg in female rats. In the subacute toxicity study, NSCH was administrated orally to both sexes of rats for 4 weeks as several doses(0, 320, 800, and 2,000 mg/kg). There were neither dead animals nor significant changes of body weights during the experimental period. In addition, no differences were found between control and treated groups in clinical signs, urinalysis, hematology, serum biochemical analysis, and other findings. Above data strongly suggest that no observed adverse effect level of NSCH might be over 2,000 mg/kg/day in this study.