Objective      To compare the bladder intramuscular nerve distribution in human and dogs.        Methods      A total of 15 fresh human bladders and 11 dog bladders were studied. Seven bladders (4 from dogs and 3 from human) were immobilized for 24 h for HE staining

and 19 bladders were immobilized with 10% formaldehyde for above 12 weeks for Sihler’s staining.        Results      The stained bladders looked like transparent jelly. The nerves were purple and entered the bladders at the ureter-bladder junction part in different forms. Human bladder nerves were more trivial

and had less branches and no ganglions in the bladder walls as compared with the dogs’. The ganglions in the dogs formed a network together with nerve fibers. The nerve fibers at both the left and right sides had little cross at the midline

and some were scattered to the lower ureter. The right nerve branches were more than the left ones in human bladder walls

while the situation was opposite in the dogs.       Conclusion      Bladder nerves scattered in the bladder walls have branches to the lower ureter from the ureter-bladder junction part. The structure and distribution of the intramuscular nerves are different between human and dog. The existence of intramuscular ganglia is correlated with the bladder function of human and dogs.