Among adrenal masses only 0.06% to 0.18% are cysts and among them, pseudocysts are the second (39%) most common lesions. Due to the increased use of imaging studies their incidence seems to have increased. Most of these lesions are incidentally found during radiologic investigation or at the time of autopsy, and only rarely they are detected in pregnant women. The latter scenario warrants emergency surgery, due to the risk of rupture. We present a case of a 39-years old woman presenting with unrelenting left flank pain due to a large adrenal psuedocyst soon after her first delivery. Four months after, she presented to our surgical division for persistent pain and anemia so underwent an extensive work up that showed a large pseudocystic mass (8 x 8 cm ) of the left adrenal gland. Once the neoplastic and parasitic etiology of the lesion were excluded, she underwent uneventful laparoscopic adrenalectomy. She was discharged home three days postoperatively. This case is the 13th case in the English literature and at the same time is the first case of adrenal pesudocyst occurred four months after delivery. Clin Ter 2012; 163(5):e331-335.