Objective To analyze the clinical characteristics and diagnostic methods of primary pulmonary cryptococcosis. Methods The medical records of adult HIV-negative patients diagnosed with primary pulmonary cryptococcosis between 2006 and March 2011 were reviewed retrospectively. Results 90 patients were enrolled in the study. The mean( ±SD) age was ( 46. 3 ±12. 42) years( range 19 to 71 years) . The clinical manifestations of pulmonary cryptococcosis were mild without obvious physical signs. The imaging features can be classified into 3 types. Nodule or mass type was common. The right lung and lower lobe were most commonly involved. There was no significant difference of the lesion type between the groups with or without underlying diseases ( P gt;0. 05) . Sputum or BALF culture for Cryptococcus neoformans yield no positive result. The main diagnostic methods were video-assisted thoracic surgery( VATS, 42 cases) , transbronchial lung biopsy( TBLB, 28 cases) and transthoracic needle aspiration biopsy( TNAB, 14 cases) . The latex agglutination( LA) test yield positive results in 31 patients out of 48 patients( 64. 58% ) . The LA test positive group often used TBLB as diagnostic method( 64. 52% ) .Meanwhile the LA test negative group and the group without LA test often used thoracoscope as diagnostic method( 47. 06% and 76. 19% ) . There was significant difference in diagnostic method between the three groups( P lt;0. 05) . Conclusions It is not impossible to acquire pulmonary cryptococcosis in immunocompetent patients. The clinical manifestations and imaging features of pulmonary cryptococcosis were lack of characteristics. The diagnosis level can be improved by invasive examination such as TBLB and TNAB. The LA test for Cryptococcus neoformans can be used as an early noninvasive diagnostic method.