This experiment was carried out to compare some carcass values of rainbow trout between purebred and crossbred, pond fish and silo fish, and between sexes. The results obtained were as follows: 1. The breeding method (purebred, crossbred) did not significantly affect body weight, but crossbred fish showed a higher carcass rate than purebred fish (p$lt;0.01). 2. As for the management practices, pond fish were superior to silo fish in their body weight, carcass weight and other body measurements such as body length, body height and body width, while silo fish showed a higher carcass rate (p$lt;0.01). 3. In comparison between sexes, male fish showed significant higher values than female fish in body weight (p$lt;0.01) and carcass weight (p$lt;0.05), although female fish had a higher carcass rate (p$lt;0.01). 4. The carcass rate tended to increase significantly (p$lt;0.05) with increasing body weight.