Abstract: Objective　To investigate the diagnosis and treatment of pulmonary alveolar proteinosis (PAP). Methods　Clinical data of 3 children with PAP admitted from 2010 to 2016 were retrospectively analyzed. Results　Three children were female and aged 3 years and 1 month, 3 years and 9 months, and 6 years and 4 months, respectively. The main symptom of the three children was cough along with or without anhelation. Two of them had longer course of disease. The therapeutic effect of conventional treatment was poor, and their chest CT indicated significant lesions. Fiberoptic bronchoscopy showed positive reaction by PAS staining, and the treatment effect was improved after bronchoalveolar lavage. Conclusions　The main clinical symptoms of PAP are non-specific cough and shortness of breath. PAS staining and bronchoalveolar lavage are of great value in the diagnosis and treatment of PAP.