Many studies have demonstrated that an autologous fat graft (AFG) can be a successful alternative to prosthetic breast augmentation; however, with the increasing use of this method, there are also increasing reports of complications. We report a case of severe infection after augmentation mammoplasty with a massive AFG. A 23-year-old woman had undergone primary AFG for breast augmentation. The remaining fat was reused for secondary graft 46 days after the primary transplantation. The patient was referred to our hospital with infectious signs on both breasts. Antibiotics were administered according to the bacterial culture result of the abscess aspirated with ultrasonography (US) guidance. During antibiotic treatment, two US-guided abscess aspirations were performed. Although follow-up magnetic resonance imaging demonstrated reduced abscess and fluid collection after aspiration, the skin of the lower pole of the right breast was perforated. We performed liposuction with real-time US guidance for abscess localization. The abscess and necrotic fat tissue were removed through liposuction. Thereafter, the symptoms, signs, and laboratory and radiologic findings demonstrated complete improvement. The patient was successfully treated while maintaining the breast contour through localized abscess removal, with a much smaller liposuction scar than would have resulted from aggressive excision or drainage.