Background: Differential diagnosis between malignant pleural effusion (MPE) and benign pleural effusion (BPE) remains a clinical challenge. Aim: to evaluate the role of microRNA (182) in differentiation between tuberculous (TPE) and malignant pleural effusion (MPE). Methods: This cross-sectional study included 60 patients admitted at the Chest Department, Benha University Hospital. Patients were divided into two groups based on pathology results: Group A (n=45): MPE and Group B: (n=15): TPE miRNA 182 was measured by qt PCR in both groups and expressed as ΔΔCT and fold change (2-ΔΔCt). Results: No statistically significant difference between MPE and TPE regarding ΔΔCT and fold change and the level did not differ significantly between malignant types. Adenosine deaminase (ADA) can significantly differentiate between malignant and TB groups (P |