Masses of the uterine cervix were detected from two dogs, being a 2-year-old female Yorkshire tarrier and a 12-year-old female Basset Hound. Grossly, the masses measuring 3.O$ imes$3.O$ imes$4.0 cm and 12.O$ imes$l2.O$ imes$10.07m were prominent, sharply circumscribed, fleshy tumors in the uterine cervix. Histologically, the masses consisted of smooth muscle cells interwoven in bundles, some of which were cut longitudinally (elongated nuclei) and others transversely. Tumor cell nuclei were ordinarily cigar shaped and had rounded blunt ends in the longitudinal plane. There were low mitotic figures without abnormal ones. From these results, these cases were diagnosed as leiomyoma of the uterine cervix. To our Knowledge, no similar tumors have been reported in the uterine cervix.