The urinary bladder is a unique organ in that its normal function is storage and release of urine, and vasculature in its wall exhibits specialized features designed to accommodate changes in pressure with emptying and filling. Although we have previously described the fine details of the microvasculature of the urinary bladder of the rabbit and dog, information on the fine details of the microvasculature of the mouse bladder were deemed to be of value because of the increasing use of this species in developing genetic models for studying human disorders. The present study shows that many of the special features of the microvasculature of the mouse urinary bladder are similar to those described in the rabbit and dog, including vessel coiling, abundant collateral circulation, arterial sphincters, and a dense mucosal capillary plexus.