Only a small amount of work has been done concerning the application ofsoil radon vapor survey with natural α-cup method to the appraisal of geo-chemical anomalies formed by gold and polymetallic ore deposits. In order toopen a new field for radon vapor survey and add a new reliable criterion tothe appraisal of geochemical anomalies, we made some preliminary tests in acertain gold anomalous area in Xinjiang belonging to semiarid steppe landscapeand the Jiaolongzhang polymetallic pyrite ore district in Gansu belonging toloessial ravine landscape. The results show that the radon vapor anomaliespinpoint satisfactorily the localities (including the concealed parts) of theknown gold mineralized bodies, and delineate several promising sectors for goldprospecting(one of them have already been verified). This demonstrates thatthe soil radon vapor with natural α-cup method can be used as one of theeffective means for delineating concealed gold mineralizations controlled bystructural fracture zones and, together with other geochemical prospecting me-thods, it may provide reliable information for finding gold-bearing structuralfracture zones. Faint radon vapor anomalies exist over the polymetallic mine-ralized zones and structural fracture zones covered with loess and Tertiary redclay some 20 m in thickness, and this suggests that the soil radon vapor sur-vey with natural α-cup method is effective in search for concealed polyme-tallic mineralizations in the loess region.