The efficient prospecting and exploration indicators of rare metal pegmatite in the eastern high coverage area is still difficult. In order to study how to delineate the mineralized pegmatite in the rare metal pegmatite in the eastern high coverage area, this studies carried out the major and trace elements of muscovite and feldspar in Yanlingguan pegmatite group in Xintai city, Shandong Province, analyzed and delineated the favorable areas of rare metal pegmatite, determined the prospecting direction by using the elemental composition and mineralization index of muscovite and feldspar, successfully found lepidolite and spodumene, and calculated the crystallization temperature of Yanlingguan pegmatite group by using feldspar thermometer. The regional zonation of Yanlingguan pegmatite group is poor, with no obvious change in lithology and mineral composition. It can be divided into Taohuayu area in the south, Tianjingyu area in the middle and Yanlingguan area in the north. The K/Rb ratio and Li of mica and feldspar show that the pegmatite dikes in Yanlingguan area have undergone highly crystalline differentiation and evolution. The conclusion that Li-rich muscovite and Cs-rich feldspar can be used as indicator minerals for lithium mineralization in the eastern high coverage area is confirmed. According to the calculation of feldspar temperature, the temperature changes are very regular when the trondhjemite in Shanggang unit and Yanlingguan pegmatite field crystallize, so the trondhjemite is the ore-forming parent rock of Yanlingguan pegmatite field.