Background: Pleural effusion is common clinical entity in day-to-day clinical practice. There are various etiologies for pleural effusion. Among those tubercular pleural effusion, parapneumonic effusion, malignant effusion, and congestive heart failure were the most common causes of pleural effusion. Here, we have done a retrospective study to see the etiology of pleural effusion in our tertiary care center. Patients and Methods: This retrospective study conducted in a tertiary care center over 1 year period. A total of 63 patients were included in this study after verifying in patient records of all patients who were admitted with exudative pleural effusion. The demographic data collected and complete history was obtained. Investigations such as complete hemogram, random blood sugar; renal function tests, serum proteins, chest x-ray, and pleural fluid analysis and investigations such as ultrasonogram of the chest and abdomen, echocardiogram, computed tomography scan of chest, fine-needle aspiration cytology, and pleural biopsy reports (if done) were collected. Results: Among the study participants, 40 were male and 23 were female patients with male-to-female ratio of 1.7:1. Mean age of the study population was 48.8 ± 18.7 years. The most common presenting symptom was dyspnea (84%) followed by cough (80%), fever (65%), and chest pain (43%). The most frequent cause of pleural effusion was tuberculosis in 38% of patients, followed by parapneumonic effusion (28.5%) and malignant pleural effusion (22.2%). Three patients had chylothorax, two patients had pancreatic pleural effusion and the diagnosis was unknown in two patients. Mean ± standard deviation (SD) adenosine deaminase (ADA) value of the study population was 45.3 ± 28.1. Mean ± SD of ADA values in tuberculous, parapneumonic, and malignant pleural effusion was 54.5 ± 16.8, 65.2 ± 30.7, and 18.2 ± 11.0, respectively. Conclusions: Tuberculosis is one of the common causes of exudative effusions along with parapneumonic effusions and malignancy. Pleural fluid ADA levels are highly sensitive with good specificity for the diagnosis of etiology of tubercular effusions. However in view of high levels of ADA in pleural fluid in parapneumonic effusions also, other measures such as clinical evaluation, lymphocyte to neutrophil ratio, and glucose levels are necessary to separate both these entities.