Jinliutan ductile shear zone locates in Shanmen Town,the east end of the North Qilian Orogenic Belt,which is the tectonic boundary between Longshan Group and Huluhe Group.LA-ICP-MS zircon U-Pb dating shows biotite amphibolite plagiogneiss from Longshan Group has formed in 461.9±7.0 Ma and granitic mylonite from Jinliutan ductile shear zone has three age groups (~460 Ma, ~420 Ma and~380 Ma). The ~460 Ma zircons are characterized by evident oscillatory zones, high Th/U ratios and left slope REE patterns with significant Ce positive anomalies and Eu negative anomalies, indicating the formation age of their protolith. Although ~420 Ma and ~380 Ma zircons have high Th/U ratios and REE patterns similar to the magmatic zircons, the internal structure exhibits weak oscillatory zone or homogeneous texture, which is the characteristics of metamorphic zircons. High Th/U ratios for the ~420 Ma zircons suggest suprasolidus conditions with monazites exhausted. ~380 Ma zircons show variable Th content and stable U content, which is distinct from the ~420 Ma zircons, indicating that Th enriched minerals (such as monazite) crystallized simultaneously during ~380 Ma zircons growth. Mylonites in the Jinliutan ductile shear zone show leucosome and melanosome bands, and some leucosome mylonites remain some irregular melanosome lens, which indicates the partial melting processes. Therefore, ~420 Ma and ~380 Ma are two episodes of partial melting occurred on the mylonites. Considering the ~440 Ma maximum sedimentary age of the Huluhe Group south to the Jinliutan ductile shear zone, the formation age of the Jinliutan ductile shear zone is limited to 440~420 Ma. In addition, the zircons of the biotite amphibole plagiogneiss from Longshan Group have positive εHf(t) values (10.26~15.13) and tDM2 of 487~790 Ma, indicating extensive continental crust growth in early Paleozoic. Zircon εHf(t) values and tDM2 ages of the granitic mylonites are -4.02~4.46 and 1120~1660 Ma respectively, indicating their source is dominated by Mesoproterozoic or more ancient continental crust. Therefore, the Longshan Group and Huluhe Group on both sides of the Jinliutan ductile shear zone can not be the source of the granitic mylonites, suggesting that their protolith has been strongly reduced during the formation of Jinliutan ductile shear zone in 440~420 Ma, which is consistent with tectonic evolution of collision and uplifting during the early Paleozoic period.