During the past five years, Pham Ngoc Thach Hospital has performed the thoracoscopy and pleural biopsy to diagnose pleural effusions that can not be made by routine techniques such as needle pleural biopsy, biology, microbiology, immunology, cytology... ect. 128 thoracoscopic cases had been performed successfully, this technique as a tool for diagnostic procedure can be considered as accurate method in chest diseases especially pleural effusions.