The Datan basin is situated in the uplift belt of the northern margin of the North China Craton and the southwest section of the Guyuan—Hongshanzi uranium metallogenic belt. A number of uranium occurrences and uranium anomaly site have been newly discovered in the Wuliying area of the basin. They mainly occurs in the middle—basic subvolcanic rocks of the Yixian period, and the geological age belongs to the late Early Cretaceous, which is obviously different from the known ore- bearing horizons in this metallogenic belt——the Zhangjiakou Formation high- potassium calc- alkaline rhyolite in the early Early Cretaceous. The rock——alkaline trachyte assemblage and the high- potassium calc- alkaline—alkaline rhyolite assemblage of the Xinmin Formation in the early Late Jurassic. However, there is still a lack of systematic research on lithology, petrography, geochemical characteristics and petrogenesis in this ore- bearing layer.Methods:Based on detailed observations of occurrence of Wuliying uranium occurrences in the field, we have studied the petrology, geochemistry, Sr—Nd—Pb radio isotope of host rocks to discuss nature of source region and tectonic setting, than, we have discussed the relationship between middle—basic subvolcanic rocks and uranium mineralization.Results:The host rock is ivernite.All of ivernites are characterized by high contents of K2O and total alkali, low contents of TiO2 and iron, and an enrichment of LREE and LILE element. It has the characteristics of alkaline series and calc alkaline series, and belongs to the typical shoshonite series. \[n(87Sr)/n(86Sr)\]i between 0. 707290 and 0. 707399(the average is 0. 707343), \[n(143Nd)/n (144Nd)\]i between 0. 511849 and 0. 511895(the average is 0. 511876),εNd(t) range of -12. 38~-11. 49, \[n(206Pb)/n(204Pb)\]i between 17. 236 and 17. 343(the average is 17. 296), \[n(207Pb)/n(204Pb)\]i between 15. 407 and 15. 428(the average is 15. 416), \[n(208Pb)/n(204Pb)\]i between 37. 666 and 37. 707(the average is 37. 684). In the εNd(t)—\[n(87Sr)/n(86Sr)\]i, \[n(143Nd)/n(144Nd)\]i— \[n(87Sr)/n(86Sr)\]i, \[n(207Pb)/n(204Pb)\]i— \[n(206Pb)/n(204Pb)\]i and \[n(208Pb)/n(204Pb)\]i— \[n(206Pb)/n(204Pb)\]i diagrams. Conclusions: The ivernite belongs to the typical shoshonite series, which shows the source of magma is closely related to EM I enriched mantle, and possibly the participation of lower crust components. Simultaneously, affected by the subduction of the oceanic crust of the Pacific plate and the delamination of the North China Craton’s lithosphere, its tectonic environment is a tensile environment, and the magma mainly originates from the partial melting of the material at the bottom of the thickened continental crust. The Wuliying uranium mineralization is similar to the "junction type" uranium deposit in the Xiazhuang orefield. Uranium mineralization occurs in a series of NNW- trending silicification and cyanidation alteration zones, and The enriched mantle imprint of its host rock, ivernite (shoshonite series), restricts the enrichment of LILE such as U.