Aim: To determine the etiological causes, radiological and laboratory features of transudative pleural effusions and to observe the clinical course after therapeutic thoracentesis. Material and Method: The files of patients with transudative effusion who underwent therapeutic thoracentesis by the Interventional Radiology Department between 01.01.2012 and 30.11.2012 were retrospectively reviewed. Pleural effusion (PE) anatomical features were evaluated with Postero anterior (PA) chest X-ray and Thorax Ultrasonography (USG). Demographic and clinical features, pleural effusion analysis results, presence and rates of complications were analyzed. Results: As a result of pleural fluid analysis, our study group consisted of 60 transudative pleural effusion cases, 36 (60%) women. The mean age was 71.23±2.36 years. Patients using diuretic therapy in cases with pleural effusion were statistically significantly higher than patients who did not (p<0.05). The most common etiologic causes were Congestive heart failure (CHF) and the accompanying disease hypertension (HT). Fifty (83.3%) of the pleural effusions were unilateral and 39 (65%) of them were right-sided (p<0.05). Diagnostic and therapeutic thoracentesis of our cases was performed by the radiologist under the guidance of thorax USG, and pneumothorax was observed in only one case (1.7%). In our 2-month clinical follow-up, the presence of recurrent pleural effusion was not detected in any of the cases. Conclusion: In cases with persistent transudative pleural effusion, therapeutic thoracentesis can be considered in cases where fluid resorption is not at the desired level despite effective treatment.