A 10-year-old, female mixed breed dog and a 3-year-old, female chihuahua which had swelling below lower eyelid were refered to Veterinary Medical Teaching Hospital, Seoul National University. The plain maxillary oblique view revealed radiolucency at periapical area in maxillary fourth premolar. The 2 cases were diagnosed as periapical abscess by clinical sign and radiographs, and apicoectomies were performed for resetting the lesions and preserving the teeth. Under general anesthesia with isoflurane, periapical abscess was resected by burs and the defect was filled with zinc phosphate cement. Radiograph was perfomed at 1 week and 1 year after apicoectomy and there was no evidence of recurrence.