When Meckel's diverticulum is a hernia content, this type hernia is called Littré's hernia. Littré's hernia is rare and has been reported only 29 cases in Japan. We described a case of Littré's hernia which was operated on in a diagnosis of incarcerated femoral hernia. A 78-year-old female complained of a right femoral tumor with sever pain without complaint of abdomen. In this reason, it was difficult to differ from lymphadenitis. Based on CT findings, the diagnosis of incarcerated femoral hernia was able to be male, leading to emergency operation. Upon operation the hernia sac was opened and incarcration of Meckel's diverticulum was found. Accordingly, resection of diverticulum and radical operation of hernia was performed. We sometimes have difficulties in the differential diagnosis of Littré's hernia from other diseases, because it has severe local symptoms compared to another type of hernia. In this case CT was valuable for the differential diagnosis.