Localised soft tissue swelling as initial presentation in child acute lymphoblastic leukemia (ALL) is extremely rare. We first report one case presenting with clitoris swellings. She was done for an abdominal biopsy from the retroperitoneal mass suspicious of neuroblastoma. Follow-up, she was eventually diagnosed with precursor B cell ALL by bone marrow biopsy, with TCF3-PBX1 fusion gene and additional chromosomal aberrations. After chemotherapy, although the girl had transiently clinical remission, the bone marrow aspirate indicated a poor outcome. Thus, this highly localised presentation is unusual and would hopefully inform clinicians to have a high index of suspicion for ALL.