Objectives: Idiopathic granulomatous mastitis (IGM) is a benign rare inflammatory pseudotumor. Bilateral involvement of IGM has been reported in a few cases. To our knowledge, this study is the largest series of bilateral cases to date. The goals of this study were to present clinical features of bilateral IGM and to evaluate the results of treatments. Materials and methods: We performed a retrospective review of the idiopathic granulomatous mastitis database from 2010 to 2013. Ten female patients who met required histologic and clinical criteria of IGM in both breasts were included in study. Demographic data, clinical findings, medication history, and radiologic findings are presented. Results: The mean age at onset of the disease was 38.4 ± 8.3 years (range: 29–52 years). Nine patients had no recurrence during a mean follow-up period of 21 months (range: 11–26 months). Additionally, the median time to second breast involvement was 15.6 months. Conclusion: Bilateral IGMs have a higher rate of more relapse and greater resistance to medical therapies than do unilateral IGMs. Surgical management should be avoided unless all medical treatment options have been exhausted. Nevertheless, expectant management seems a rational option for the treatment of bilateral IGM.