A 65-year-old woman who had undergone surgery for rectal cancer was referred to our hospital with an abnormal shadow on chest X-ray. Chest computed tomography (CT) revealed a 3-cm-diameter mass with ill-defined margins in the left lower lobe and a well-defined, 1-cm-diameter, round nodule in the right upper lobe. Transbronchial lung biopsy (TBLB) of the left lung tumor revealed metastatic adenocarcinoma originating from the rectal cancer. The patient underwent synchronous partial resection of the right upper lobe and left lower lobectomy under video-assisted thoracoscopic surgery (VATS). The pathological diagnosis of the right lung tumor was chondromatous hamartoma, and the left lung tumor was metastasis originating from the rectal cancer. The patient's postoperative course was uneventful, and she was well and free of disease 4 years after pulmonary metastasectomy.