Abstract: In order to study the intrinsic correlation of body weight and body measurement traits in Siming chickens, the body weights and traits of cocks at day 91 and hens at day 119 were measured and analyzed by principal component analysis. The results showed that average values of body diagonal length, keel length, chest width, chest depth, pelvis width, shank length, shank girth, body weight of cocks were 1884, 1057, 753, 909, 606, 851, 435 cm and 1 59113 g, the values of hens were 1818, 1072, 730, 824, 632, 720, 396 cm and 1 64833 g, respectively; the cocks body weight was highly significantly correlated with body diagonal length, keel length, chest width, pelvic width (P<001); the hens body weight was highly significantly correlated with body diagonal length, shank length, shank girth (P<001), and was significantly correlated to the chest width and chest depth (P<005). The contribution rate and characteristic root of the main components indicated body weight, body diagonal length, chest width and shank length play important roles. Our results suggested that at least above four indexes should be included in breeding of Siming chickens for the body size. The results would contribute to the breeding and production of Siming chickens to some degree.

Key words: Siming chicken, body weight, body measurement traits, principal component analysis