Abdominal involvement in an isolated extramedullary relapse region in patients with acute lymphocytic leukemia (ALL) is a rare event, especially in patients in hematological remission. The literature related to this subject is very limited. In this study, a 23-year-old male patient, is presented who had been in remission for 4 years, was admitted because of an enlarged testis, and was found to have an abdominal bulky mass during physical examination. An early diagnosis of abdominal involvement is extremely important and must be kept in mind for ALL patients who are admitted for testicular relapse.