Providing a therapeutic agent for lung disease which is highly effective and has a small side effect. A therapeutic agent for pulmonary disease for intracorporal administration containing biocompatible polymer nanoparticles comprising an HMG-CoA reductase inhibitor.유효성이 높고, 또한 부작용이 적은 폐질환 치료약의 제공. HMG-CoA 리덕타아제 저해제를 포함하는 생체 적합성 폴리머 나노 입자를 함유하는 기관 내 투여용 폐질환 치료약.