Several biomarkers of tuberculous pleurisy, including ADA and IFN-γ, have been evaluated to help early diagnose the disease. Objectives: To evaluate the value of ADA and IFN - γ in the diagnosis of TB pleural effusion. Method: A total number of 100 patients with lymphocytic exudate pleural effusion admitted to Cho Ray hospital and Pham Ngoc Thach hospital were taken into the study.