A simple technique for catheterization of the urinary bladder of cattle and buffalo calves before and after separation of glans penis was described. The study was classified into two main parts. Part I was experimentally conducted on 10 cattle and 10 buffalo calves and each group was subdivided into 5 animals with and 5 animals without separation of glans penis, and it was used for determination of the ease of retrograde catheterization of the urinary bladder. Part II was clinically conducted on 47 cattle and 5 buffalo calves either for diagnosis or treatment of certain affections. Results revealed the easy catheterization of the urinary bladder in 91% of cases after 1-2 trials, and that one successful retrograde catheterization requires 1.4 trials. It was observed that the catheterization was more difficult in buffalo calves than cattle ones. The technique was useful for diagnosis and treatment of certain affections of urinary tract in cattle and buffalo calves.