Abstract: Aggressive angiomyxoma (AAM) is a rare soft tissue tumor typically in the pelvis and perineum in women of reproductive age, which is easily misdiagnosed. We describe a woman with vulvar AAM, initially mismanaged as a Bartholin cyst. However, a huge pelvic mass is noted on the following imaging studies. The characteristics of AAM on computed tomography and magnetic resonance imaging have been specified in the literature, but we further point out the potential value of sonography in diagnosing AAM. Besides, excisional biopsy may cause tumor bleeding in a case of AAM.