Tailgut cysts are known to originate from the remnants of the embryonic hindgut. They occur exclusively in the retrorectal and presacral spaces. There have been limited reports of tailgut cysts occurring in the left perirenal space. The present case features a huge tailgut cyst extending from the right perirenal to the perivesical space. We believe that this case report will help to further elucidate the characteristics of perirenal and perivesical tailgut cysts.