Simultaneous bilateral spontaneous pneumothorax (SBSP) is a very rare condition, mainly seen in patients with underlying lung disease. Up to now, there are 65 patients who have been published. Twelve consecutive patients who presented with SBSP as definitive diagnosis were recruited for this study. They represented 1 % of all patients with spontaneous pneumothorax. All patients had immediate bilateral chest tubes on admission. Five of the 12 patients (42%) had no underlying lung disease. In 7 patients, SBSP was secondary to pulmonary metastases, histiocytosis X, undefined interstitial pulmonary disease, tuberculosis, pneumonia and chronic obstructive pulmonary disease. None of the patients died during hospitalization. Eleven patients were treated with chemical pleurodesis, whereas thoracotomy and pleurectomy were necessary in 7 patients. Reexpansion of the lungs was achieved in all patients. Immediate bilateral chest tube insertion and pleurodesis are of major importance in the treatment of SBSP although a subset of patients needed surgical pleurectomy. Combination of these treatments provides successful and uneventful treatment of the disease.