We report a case of drug-induced pneumomediastinum by bleomycin in testicular cancer, which is extremely rare ; to our knowledge, only 3 cases have been reported. A 28-year-old man presented with a left testicular mass. He underwent radical left inguinal orchiectomy that demonstrated a seminoma, pT3N0M0. Ten months after surgery, para-aortic lymph node metastasis appeared, and he received three cycles of bleomycin, etoposide and cisplatin (BEP) chemotherapy. On day 13 of the fourth course of BEP, he complained of snowball crepitation of the neck and computed tomography revealed subcutaneous emphysema, extensive mediastinal air, and intraspinal air accumulation without pneumothorax. The pneumomediastinum and subcutaneous emphysema tended to deteriorate until 15 days after the onset of pneumomediastinum, but fortunately he had no signs or symptoms of infection. These findings resolved spontaneously after 1 month.