The invention discloses a method for measuring and calculating milk yield of Ili horses by utilizing body size traits and an adopted program. 11 common body size trait indexes, namely body height, chest width, chest depth, rump width, rump angle, udder depth, udder attachment height, nipple length, nipple diameter, front section and waist strength of the Ili horses are taken as udder traits, have a relatively close relation with the milk yield and are representative, a regression equation is established for the milk yield, an equation established by the body size traits is taken as the basis, and then a computation program is obtained by conversion so as to facilitate recording and operation of data and be capable of being applied to scientific measurement and calculation of the milk yield of the Ili horses. According to the method disclosed by the invention, the difficult problem of great collection difficulty of the milk yield in the traditional method is solved, the Ili horses are selected through a regression model, the level of the milk yield of the Ili horses is ordinarily improved, and the relatively high workload of traditional manual recording is overcome, so that the method has a practical effect in facilitating measurement and calculation of the milk yield of the Ili horses in practices and further has an extensive practical application value.