This paper reported a case of 77-year-old male patient who developed generalized ery-thematous macules,bullae and erosion,accompanied by genital mucosa involvement five days after taking compound sulfamethoxazole tablets.Based on patient's clinical manifestations and auxiliary ex-amination results,the diagnosis of generalized bullous fixed drug eruption was confirmed.Clinicians should be vigilant about generalized bullous fixed drug eruption with genital mucosa involvement and strive for early detection,diagnosis,and treatment.