Abstract: Objective: The study aims to explore the correlation between the amount of chylothorax and HRCT appearance of lung cyst lesions for LAM. Materials and Methods: 36 LAM with chylothorax patients proved by pathology or clinical results were included in the investigating group. HRCT were performed for all the patients. The imaging manifestations were analyzed by 2 doctors, including (1) grades for the amount of chylothorax: grade I, small size; grade II, middle size; grade III, large size. (2) cyst size, cyst involvement area, HRCT severity grades of pulmonary cyst lesions. Analysis of variance was used in the statistical analysis. Results: There is no relationship between the amount of chylothorax and cyst size, and cyst involvement area, and HRCT severity grades of pulmonary cyst lesions. Conclusions: The amount of chylothorax is decided by many factors, and which is related to the etiology of chylothorax of LAM. The amount of chylothorax cannot be used to evaluate the severity of pulmonary cystic lesion involvement for LAM.