The reproductive system of the female red kangaroo consists of paired ovaries, Fallopian tubes, and uteri. The uteri open on separate papillae into the anterior vaginal sinus. An incomplete septum divides the right and left halves of the vaginal culs-de-sac at the first oestrus. Size changes in the parts of the reproductive system of females in the immature, oestrous, post-oestrous, luteal, post-luteal, pro-oestrous, and quiescent stages of the reproductive cycle are described and illustrated, and measurements of the various parts are presented in tabular form. A Graaffian follicle of 5-6 mm diameter is present in one ovary at oestrus. At this stage there is mitotic proliferation in the uterine epithelia and cornified cells are found in the epithelia of the posterior parts of the vaginal complex. Mitotic proliferation continues in the uterine epithelia after oestrus. During the luteal phase a corpus luteum of 6-8 rnm diameter is present, the uterine glands are well developed with high columnar epithelium and basally situated nuclei, and mitoses do not occur in the uterine epithelia. Regression of the hteal phase is followed by pro-oestrus in both pregnant and non-pregnant females.