In 5-year male m811ese, was showed aggressive bebavior, $1.5{ imes}1.0 cm$ mobile mass that was located in right iinguinal area was unilaterally palpated, and the dog was appeared no pain. In the ultrasonography, there was a 41.26{ imes}119 cm$ oval hypo-echogenic mass. In the histopathohgic examination, testicular hypoplasia was observed but there was not any evidence of development of neoplasia. In bilateral cryptorchidectomy, descended testis near the left side of prepuce was incised and the retained testis directly incised and eliminated by closed method. After operation, there was a good prognosis without hemorrage and inflammation.