We treated 8 cases of autoimmune pulmonary alveolar proteinosis (APAP) with whole lung lavage (WLL) in our hospital and evaluated the disease severity of APAP before and after WLL, adverse events (AEs) and recurrence-free survival in those cases who improved. In all cases, unilateral WLL was performed in both lungs. The median of total lavage volume in unilateral WLL was 17.9 L, and the median procedure time of unilateral WLL was 105 min. Fever was the most frequently observed AE (87.5% of all procedures). Pulmonary function tests (percentage of predicted value of VC, FEV1 and diffusing capacity of carbon monoxide), serum markers (KL-6, surfactant apoprotein (SP)-D, SP-A and carcinoembryonic antigens), arterial blood gas analyses (PaO2, AaDO2) and disease severity score all significantly improved after WLL. The serum levels of anti-granulocyte-macrophage colony-stimulating factor (GM-CSF) antibody temporarily decreased after unilateral WLL, but returned to previous levels (before WLL) in 7 cases. The radiological findings improved in 6 cases. In the 7 improved cases in whom AaDO2 decreased more than 10 Torr, the median recurrence-free survival of APAP after WLL was 17.5 months. We concluded that WLL is an effective and safe method for the treatment of APAP, and all parameters except for anti GM-CSF antibody are useful to evaluate the effect of WLL.