Based on a vast mount of data on regional geology, petrology and geochemistry, the authors present a number of major data about the Xionger Group, and expound the authors's views about the points at issue. Meanwhile, they point out some issues which merit a detailed study in the future. The study shows that the Xionger Group volcanics consist dominantly of shoshonites, latites, trachydacites and rhyolites with subordinate high-K basaltic andesites, high-K andesites and high-K dacites. Volcanic rock series include mainly the shoshonite series and subordinately the high-K calc-alkalic series. The Xionger Group possibly reveals the product of the extensional stress setting) however, the geochemical characteristics of the volcanic rocks appear to demonstrate that the subcontinental litho-spheric mantle may have experienced the concentration process of subduction zone components (SZC) during the Xionger Stage or prior to the Xionger Stage, and thus, the Xibnger Group volcanics may be assigned to the backarc rift volcanics behind the continental-margin arc or lag-type arc volcanics.