Abstract: An inhalation formulation for treating an IPF disease. The inhalation formulation is an aerosol inhalation liquid formulation, an inhalation aerosol, a dry powder inhaler or a soft mist inhaler. The inhalation formulation contains an active drug, and the active drug is any one of apremilast, ibudilast, roflumilast, crisaborole, and difamilast. A preparation process for the inhalation formulation is introduced into a conventional formulation. An active component in a conventional oral formulation is prone to being destroyed in the digestive tract, and has low bioavailability, a liver first pass effect, and a slow onset of action. An inhalation formulation capable of significantly alleviating IPF is prepared. Tests prove that the prepared inhalation formulation can effectively increase the bioavailability, and improve the clinical use effect.