Published data have shown that the levels of vascular endothelial growth factor (VEGF) and soluble VEGFreceptor-1 (sVEGFR-1) in plasma and pleural effusion might be usefulness for lung cancer diagnosis. Here, weperformed a prospective study to investigate the utility of VEGF and sVEGFR-1 in bronchoalveolar lavage fluid(BALF) for differential diagnosis of primary lung cancer. A total of 56 patients with solitary pulmonary massedby chest radiograph or CT screening were enrolled in this study. BALF and plasma samples were obtained fromall patients and analyzed for VEGF and sVEGFR-1 using a commercially available sandwich ELISA kit. Theresults showed that the levels of VEGF in BALF were significantly higher in patients with a malignant pulmonarymass compared with patients with a benign mass (P < 0.001). However, no significant difference of sVEGFR-1in BALF was found between malignant and non-malignant groups (P = 0.43). With a cut-off value of 214 pg/ml,VEGF showed a sensitivity and specificity of 81.8% and 84.2%, respectively, in predicting the malignant natureof a solitary pulmonary mass. Our study suggests that VEGF is significantly increased in BALF among patientswith lung cancer than in benign diseases. Measurement of VEGF in BALF might be helpful for differentialdiagnosis of primary lung cancer.