AbstractWe Report a case of Idiopathic granulomatous mastitis in a 30 year old pregnant woman who came to our hospital with complaints of painful lump in her right breast because the results of initial aspiration cytology was mammary abscess with focal mastitis, incision and drainage was performed when MRI breast showed intermediate concern for malignancy – Excision biopsy was done. However the final histopathological diagnosis was granulomatous mastitis with no evidence of malignancy. A review of literature revealed that idiopathic granulomatous mastitis has a tendency to affect young woman with a history of child birth on oral contraceptive usage. Clinical diagnosis and imaging has often been difficult. Complete resection or corticosteroid therapy can be recommended as appropriate treatment. Since recurrence rate is as high as 50%, long term follow up is indicated in such patients.