A pregnant woman was referred to our perinatal tertiary care centre because of foetal bowel distension. Ultrasonography revealed a well-circumscribed circular mass in the foetus’ abdomen. After delivery, the male neonate underwent laparotomy to excise the mass. Pathologic examination of the mass was consistent with the diagnosis of foetus in foetu. This case of foetus in foetu was differentiated from a teratoma based on the presence of a vertebral axis and appropriate arrangement of other organs and limbs relative to the vertebral axis. A multidisciplinary clinical approach may be more suitable for managing rare foetal disorders, such as this one.