An intact female Maltese dog, rescued two months previously, and weighing 2.7 kg, was presented for ovariohysterectomy. There were no typical clinical signs and evidences of parturitions. A firm abdominal mass was palpated, which was identified as a round-shaped radiopaque mass in survey radiography. The mass was tentatively diagnosed as an extrauterine foetus with mummification on computed tomography (CT). Surgical removal of the mass and ovariohysterectomy were performed. Histopathological examination yielded a final diagnosis of abdominal ectopic pregnancy.