PURPOSE: A composition containing a platinum nanoparticle for preventing or treating post-menopausal metabolic diseases is provided to reduce increase of subcutaneous and visceral fat after menopause. CONSTITUTION: A pharmaceutical composition for preventing or treating metabolic diseases contains a platinum nanoparticle as an active ingredient. The platinum nanoparticle is prepared by wire explosion of platinum. The metabolic diseases include post-menopausal obesity. The platinum nanoparticle reduces increase of subcutaneous and visceral fat after ovariectomy. A health food for treating metabolic diseases contains the platinum nanoparticle as an active ingredient. A platinum suspension with excellent dispersion is prepared in distilled water through wire explosion by applying voltage to a wire with a length of 0.1 mm at 3kV.본 발명은 백금 나노입자를 유효성분으로 포함하는 대사성 질환 치료 또는 예방용 조성물에 관한 것으로, 보다 상세하게는 상기 백금 나노입자는 난소절제술 후의 체중 증가와 피하 및 내장 지방 증가를 감소시킴으로써 대사성 질환 특히, 폐경 후 비만의 치료 또는 예방에 매우 유용하게 사용될 수 있다.