This experiment was carried out to develop a chemical castration with a single intratesticular injection of silver nitrate solution in domestic rabbits. A total of 44 bucks of 4 to 5 months old were alloted at random into the following 4 groups: 9 bucks for controls, 6 bucks for 0.3㎖ injection of 1% AgNO₃, 14 bucks for 0.5㎖ injection of 1% AgNO₃ and 15 bucks for 0.5㎖ injection of 5% AgNO₃. Changes in body weight, testicular width in scrotum. weight and histology of testis at necropsy, blood cell counts and plasma levels of testosterone of the buck were measured for 4 weeks after treatment. The results obtained were summarized as follows: Compared with the controls, the body weight gain of bucks treated with AgNO₃ was not significantly (P$lt;0.05) different during the experimental period for 4 weeks. The white blood cell counts were tended to be increased slightly but insignificantly 1 day after injection of AgNO₃ and then decreased to normal level soon. There was no significant change in red blood cell counts in the bucks treated with AgNO₃. Most of the testis of bucks were swollen significantly (P$lt;0.05) by 6 to 12㎜ in the width of testis in scrotum 1 day after injection of AgNO₃, but began to decrease in sue from 3 days after treatment and to their normal size in a week. The AgNO₃ injection was not sufficient to castrate some bucks successfully. Only 60.0 to 66.7% of the bucks treated with 0.0㎖ of 1 or 5% AgNO₃ solution showed the plasma levels of testosterone of !sower than 0.1 ng/㎖ by 28 days after treatment. This result was considered to be due to the fact that not a whole but a limited part of testis was injured by the present method of injection. The weight of testis of the bucks of which plasma testosterone were less than 0.1 ng/㎖ by 7 to 28 days after treatment was not significantly(P$lt;0.05) different between the treatments or periods after treatment. This result indicates that the period of 4 weeks following treatment might be insufficient for the injured testicular tissue to be necrotized and absorbed fully. The extent of damage of testis by injection of AgNO₃ was much different by the local effect in the parts of distance from injection. The proximal portion of testis injected with AgNO₃ was fully damaged and necrotized, but a distal part of testis was not severely damaged.