Conventional laboratory assays proved various levels of sensibility in diagnosis of TB pleural effusion (TPE), which is challenge in early case-detection. The study aim was to establish the role of laboratory criteria in diagnosis of TPE. Material and methods: 69 adults diagnosed with TEP with a single disease localization through clinical-radiological-laboratory tests during 2019-2022 in Chisinau was conducted. Results: male-female ratio was 3,2/1, age between 18-24 yo was established in 5(7%), 25-44 yo 38(55%), 45-64 yo 16(23%) and over 64  yo in 10(15%) cases. The clinical onset was acute less than 7 days in 44(64%) and between 7-30 days in 25 (36%) cases. Thoracocenthesis was performed, which extracted an exudate <0.3 L in 11(15%), 0.3-0.5 L in 24(50%) and >0.5 L in 34 (35%), with cytology exam revealing the share of lymphocites within the range 81-00% in all cases. Pleural activity of adenosine deaminase (ADA) was above 40U/L in 45(65%) and positive Light's criteria were identified in 59 (85%). All patients were new cases detected by symptomatic case-finding. Chest XRay reveald the location in right hemithorax in 49(71%), in left in 20(29%) and associated with pleural adherence in 7(10%) cases. Positive for AFB was 1(1%) case, conventional cultures for MBT in 8(12%), including 1(1%) MDR-TB, and Xpert MTB/Rif in 9(13%)cases. Treatment success was obtained in 62(91%) and were still continuing the treatment 7(9%)cases. Conclusions: fluid cytology, ADA and Light's criteria provided the major role in diagnosis of TPE.