Summary. Sheep antisera were prepared against saline extracts of rabbit ovary, oviduct and uterus. The Ouchterlony double diffusion technique was employed to detect the antigens specific to the reproduc- tive tissues in these organs. The unabsorbed antisera produced the following numbers of precipitin bands : anti-ovary versus ovary, fifteen bands; anti-oviduct versus oviduct, twelve bands; anti-uterus versus uterus, ten bands. Absorption of each of the three antisera by rabbit plasma, kidney and spleen was necessary to detect antibodies directed against antigens specific to the reproductive tissues. The following num- bers of precipitin bands were observed when such absorbed antisera were allowed to react against the homologous tissue : anti-ovary versus ovary, two bands; anti-oviduct versus oviduct, six bands; anti-uterus versus uterus, two bands. The absorbed antisera produced no bands against any of the seventeen non-reproductive tissues or testis extract. Based on the sensitivity of the Ouchterlony technique and the number of non\x=req-\ reproductive tissues examined, these results were interpreted as indi- cating that the rabbit reproductive system contains tissue-specific anti- gens. In the ovary, the tissue-specific antigens were restricted to that structure. Several of the tissue-specific antigens detected in oviduct and uterus, however, were also present in the other reproductive tissues.