The sexual steroid receptors of the genital tract of the female have significant importance since though them the hormones responsible acting. In their mechanism one of the factors to be kept in mind is the possible differences among the diverse species, the objective of this study was to evaluate in canine (N= 8) the presence of receptors of estrogens (ER), progesterone (PR) and the presence of corticosteroid binding globuline (CBG) in ovaries, oviduct and uterus of prepuberal female (N=-3) and matures: (N=5) It was used WE and immunohistochemical study according to the technique of Stenberger (1979). The results during the oestrus showed: Immune reactivity (IR) positive, ER in uterus and ovary being much stronger in oviduct. The PR varied according the stage of oestrus cycle. In puberal female dog ER and PR were undetectable. The CBG revealed positive in reproductive tract of cycling females but negative in prepubertal. It was concluded that the presence of ER and PR are detectable in uterus, oviduct and ovary of mature female dogs varying their concentration according to the cycle. In prepuberal, its presences come undetectable differing from other species (ovine), in which they are detected at this stage of development. The constant of CBG presence during oeustrus cycle and such variation in other stages of the cycle, it might suggest its participation in the several reproductive activities.