In order to find out the distribution characteristics of rare elements, the genesis of pegmatite and deep prospecting potential of Lijiagou spodumene deposit in Jinchuan County, Sichuan Province, statistical analysis of rare elements from ore-bearing pegmatite, barren pegmatite and wall rock in exploration trenches and drill holes on No.2, 5, 9 and 11 from exploration lines from east to west in the largest No.Ⅰ vein of Lijiagou spodumene deposit, and in situ crystallization simulation calculation was conducted on the Ke'eryin two-mica granite and the ore-bearing pegmatite of No.Ⅰ vein. The analysis results show that the main rare element in No.Ⅰ vein is Li, accompanied with Be, Rb, Sn, Nb and Ta, which have similar characteristics to the rare element in the Jiajika X03 vein. The metallogenetic elements distribution regularity of the No.Ⅰ vein from top to bottom is that Li is enriched in the upper part, Be is enriched in the middle part, Nb and Rb are enriched in the lower part, while Nb and Rb in the Jiajika X03 vein are relatively enriched in the upper part of the ore body. The in situ crystallization simulation calculation indicated that the No.Ⅰ vein of Lijiagou was not formed by crystallization differentiation of a set of magma systems that formed Ke'eryin two-mica granite. The petrogenesis mechanism of the pegmatite of Lijiagou spodumene deposit may be that the first step is the low degree partial melting of the metamorphic sedimentary rock to generate relatively Li rich melt, followed by further enrichment of the melt through crystallization differentiation to form Li saturated melt, and finally crystallization to form spodumene pegmatite.