Charcoal remains stable without causing a foreign body reaction and it may be used for preoperative localization of a non-palpable breast mass. However, cases of post-charcoal-marking granuloma have only rarely been reported in the breast, and a charcoal granuloma can be misdiagnosed as malignancy. Herein, we report the ultrasound, computed tomography (CT), 18F-fluorodeoxyglucose-positron emission tomography/CT, and breast-specific gamma imaging findings of recurrence-mimicking charcoal granuloma after breast conserving surgery, following localization with charcoal in a breast cancer patient.