Objectives: In the Songpan orogenic belt, Indosinian granitoids are widespread. These granitoids provide significant insight into the regional tectono—magmatic events, basement nature and tectonic evolution. Methods: In this paper, we present wholerock major and trace elements, Sr—Nd isotopic compositions of the Guanyinqiao twomica granites in Jinchuan area from the eastern part of the Songpan orogenic belt  Results:The granites are peraluminous highK calcalkaline Stype granites, with high SiO2（72.08%~73.95%）、K2O（4.44%~5.84%）and Na2O （3.29%~3.93%）contents, A/CNK=1.08 ~1.22。The granites exhibit an enrichment in large ion lithophile elements and a depletion in part of high field strength elements as well as a prominent negative Eu anomalies（δEu=0.26~0.38）.Their εNd(t) is -7.9 to -10.1（average value is -8.9）, and T2DM（Ga） varying from 1.45 to 1.57Ga, suggesting a Mesoproterozoic crustal origin. Conclusion: In combination with the geochemical characteristics, isotopic analysis results and regional geological data, we propose that the Guanyinqiao twomica granites were derived from the argillaceous source region. The granites were formed in the compressive tectonic setting during the postcollision of fold orogenic in Songpan orogenic belt.