To understand the genesis of uranium deposits in different ore hosting rocks and discuss the relationship between deposits and tectonic geological setting of Xinlu volcanic basin in Quzhou city, Zhejiang province, we have focused on Jiuhuashan granitic volcanic-intrusive complex by zircon U-Pb geochronology，major and trace element analysis, and Sr-Nd isotopic analysis. SHRIMP U-Pb dating of zircon grains from the volcanic and intrusive rocks yield ages of 134.9~137.8 Ma, and both of them have similar geochemical characteristic with high Al (11.96 %~14.59 %), Na 2 O+K 2 O (7.35 %~9.30 %), Zr+Nb+Ce+Y (>350), FeO*/MgO (>10) and Ga/Al ratio (>2.6×10 -4 ), indicating that they are products of a synchronous magmatism with a typical characteristic of aluminous A-type granite. While those more acidic rocks have lower Zr and P contents, more enrichment in some LILEs，and more depletion in Ba、Ta、Nb、Ti and Eu, which announces a varying degree fractional crystallization in magma source. The isotope geochemical characteristics display young and dispersed Nd model age, high $\upvarepsilon$ Nd (t ) values in the range of -6.16 to 2.26, suggesting an input of mantle materials. We conclude the volcanic and intrusive rock formed in the same magmatic event which occurred at a tectonic setting of extension and upwelling of asthenosphere in Xinlu basin in early Cretaceous, and it provides a favourite ore-controlling structure, material source and heat for uranium mineralization. This also means those uranium deposits in different ore hosting rocks have similar genetic~mechanism.
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