A prospecitive study was performed to evaluate the efficacy of Radionuclide Hysterosalpingogra- phy (RNHSG), that was modified by McCalley, et al. for the evaluation of fallopian tube. Using spontaneous migration of Tc99rn labelled human albumin microsphers (HAM) and images got with Gamma camera, the study was made in 20 gynecological patients (44 tubes) in an effort to confirm the anatomical patency or obstruction as well as functional one at the Department of Obstetrics and Gynecology, NationalMedical Center from January 1, 19B6 to July 31, 1986. The efficacy vas also compared with that of contrast hysterosalpingography and surgical observa- tl.Otl. Results obtained were as follows; 1) The Radionuclide Hysterosalpingography appeared to be a simple and accurate procedure as a mean with which anatomical tubal patency, as well as functional patency can be detected, although its some limit in showing anatomical details of uterine cavity and tubes in comparison with contrast hysterosalpingography. 2) 1'he predicted value of tubal obstruction was 82.4%, and that of tubal patency was 88.9% respectively. Overall efficacy (percent of tube correctly classified) r>f Radionuclide Hysterosalpingography was 88.6%. 3) There was no nuclide related complication during and after the procedure.