Abstract: In order to study microstructure,high temperature oxidation resistance of Fe-based, Cr3C2/Fe composite coating, as well as phase structure evolution of Cr3C2/Fe composite coating, Fe-based alloy and Cr3C2/Fe-based alloy composite coatings were obtained on Q235 whose composition is similar with Fe-based alloy with a SkW CO2 laser.Then relevant test data were obtained and theoretical analysis was conducted.Results show that; the Fe-based alloy coating is mainly composed of phase α-Fe, Cr23C6,as well as the body-centered cubic α-Fe solid solution, etc.;the cladding layer mainly crystallizes in sub-eutectic crystallization way, there exists lamellar eutectic crystal organization between the primary solid solution.The main composition of Cr3C2/Fe-based alloy composite coating are γ-Fe,α-Fe, Cr23C6,Cr3C2,Cr7C3 and so on. The Fe-based alloy coating is composed of well-developed c-Fe dendrites and the eutectic structure during the composition, Cr3C2/Fe-based alloy coating typical organizations are equiaxed grains, as well as small eutectic. Cr3C2 pairs play a major role in promoting the organization from dendrite to equiaxed transformation; Cr3C2 can significantly increase the micro-hardness, high temperature oxidation resistance and other physical properties of Fe-based alloy coating. The results have certain assistance for subsequent Fe-based alloy laser claddinc and laser surface modiCcation.