A murine monoclonal antibody, 130-22, produced against a human lung adenocarcinoma cell line (PC-9) has been suggested as recognizing an antigenic determinant (CA130) which is different from an epitope recognized by OC125 on CA125 glycoprotein molecules. The immunohistochemical reactivity with the 130-22 antibody (anti-CA130) was examined in human fetal tissues, and normal and neoplastic tissues of female genital tracts, and compared to those using OC125. Among the fetal tissues, the amnion and the cells of coelomic epithelium and mullerian-derived epithelia reacted with anti-CA130. In normal adult tissues, cervical and endometrial gland cells, tubal epithelial cells, and ovarian surface cells reacted with anti-CA130. In addition, predecidual cells in the late secretory endometrium and decidual cells during gestation were positive. Among the neoplastic tissues, tubal and endometrial adenocarcinomas and epithelial ovarian tumors were positive for anti-CA130. There were no differences in the respective specimens between the immunohistochemical localization of anti-CA130 and of OC125. Therefore, anti-CA130 is considered to be useful in the immunohistochemical detection of CA125 glycoprotein molecules as well as OC125.