Hepatic mesenchymal hamartoma is a rare hepatic tumour seen in the paediatric population. Although this entity has a variable imaging appearance, it has a favourable prognosis if diagnosed and managed correctly. This case presents the ultrasound and computed tomography findings of an 11-month-old patient who presented with a history of progressive abdominal distension and an elevated alfa fetoprotein level on biochemistry. The case describes how a confident perioperative diagnosis could be made on the basis of characteristic imaging features.