The aim of this study was to describe a minimally invasive thoracoscopy to obtain lung biopsy in less than 5-kg patients. Ten rabbits were used as experimental models. A two-port thoracoscopic approach was carried out. For lung biopsy, we used a simple pre-tied loop ligature ("miniloop") based on Meltzer's knot for prophylactic hemostasis and pneumostasis. Paraxiphoid transdiaphragmatic approach to the first 6-mm trocar was placed beside the base of the xiphoid cartilage between the xiphoid process and costal arch. A 5-mm rigid endoscope was inserted through this trocar. The second trocar was introduced in the 9th intercostal space. A Babcock forceps was used for pulmonary arrest, and the miniloop system was introduced percutaneously, perpendicularly cranial to the second portal. After lung ligation, the distal lung portion was sectioned by endoscopic scissors. The miniloop system was effective for air leakage and hemorrhage after lung biopsy. A margin of the pulmonary parenchyma 2 to 3 mm distal to the ligature was left to avoid slipknot. The mean of total surgical time was 35 minutes, and obtained tissue sample sizes averaged 0.7x1x0.4 cm. Preoperative and postoperative radiographs were performed and compared in order to verify the absence of pneumothorax and hemothorax. Necropsy was performed on the 15th day after surgery for analysis of the pleural cavity. Macroscopic changes occurred as the presence of pleural fluid in small quantities and intrathoracic adhesions were observed in three animals, but these changes did not affect the effectiveness of the technique.