Calyceal diverticula are rare outpouchings of the upper collecting system that likely have a congenital origin. They are usually single cystic lesions accompanied by stones inside them and located in the upper pole calyces. We present a case containing a petal-like cystic lesion with multiple septa in the lower pole of the left kidney, which was confirmed as calyceal diverticulum by computed tomography urography and intraoperative findings.