Pulmonary vein thrombosis is a known complication after lung transplantation but has rarely been reported after lobectomy or bilobectomy. We report the case of a left upper pulmonary vein thrombosis following an uneventful left lower lobectomy for bronchial carcinoma. Postoperative arterial blood gas values and chest radiographs were normal. On postoperative day 5, the patient became progressively dyspneic, developed hemoptysis and showed total opacification of the left lung without mediastinal shift on chest radiography. The patient remained dyspneic despite intravenous antibiotic therapy for suspected pneumonia and absence of obstruction at bronchoscopy. Diagnosis of left upper pulmonary vein thrombosis was finally made by contrast-enhanced multislice computed tomography followed by pulmonary angiography. Further clinical deterioration under conservative treatment forced us to remove the remnant left upper lobe that already showed gangrenous alterations. Pulmonary vein thrombosis following lobectomy or bilobectomy is very rare. Only 7 cases have been reported in the literature so far. Conservative treatment with antibiotics and anticoagulants may be successful but in case of clinical deterioration the affected lobe has to be resected. The mechanism of thrombosis remains unclear although intraoperative torsion and injury of vessels seem to be most likely since pulmonary vein thrombosis occurred in the operated hemithorax only.