The petrological characteristics and zircon U-Pb geochronologic data of a newly recognized Eo-Paleoarchean gneiss complex in the Anshan area was presented in this study, aiming to investigate the formation and evolution process of the early Archean crust. The complex were widely distributed across the region, mainly as enclave within the ~3.1 Ga fine trondhjemite. The complex were composed of Eoarchean trondhjemite/quartz-diorite and Paleoarchean gneiss complex. The former one is enclosed by the latter as enclaves. The Eoarchean trondhjemite/quartz-diorite mainly preserved igneous textures, but was partly altered by subsequent metamorphism. Their ages are dated to be 3.77~3.81 Ga and their zircon εHf(t) values are positive, indicating that they represent juvenile crust that originated from partial melting of basaltic rocks. Paleoarchean gneiss complex are composed of banded gneiss, light-color trondhjemitic gneiss, biotite schist and a small amount of amphibolite. They show complex and heterogeneous textures, and were altered by ductile deformation, which possibly formed in metamorphism-anatexis event at a deep crustal level. The Paleoarchean gneiss complex formed simutaneously at 3.29~3.36 Ga and their zircon εHf(t) values are all negative, indicating that they formed from re-melting of an Eoarchean ancient crust. In conclusion, the Eo-Paleoarchean gneiss complex recorded multiple magmatic-tectonic thermal events at ~3.8 Ga, 3.7~3.4 Ga and ~3.3 Ga, in which ~3.8 Ga and ~3.3 Ga respectively represent two major phases for crustal growth and re-melting. Result in this study implies that multistage crustal growth and re-melting was possibly a dominant mechanism and process for early-stage crustal evolution, which is similar to that revealed from Archean terranes worldwide.