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In this study, high-density CoCrMo and Cr3C2/CoCrMo alloys were prepared by selective laser melting (SLM) to investigate the effect of Cr3C2 particles on the microstructure, strength and wear resistance of the CoCrMo alloys. It was found that the phases of the alloy were γ-Co and ε-Co, and the M23C6 phase was generated due to the addition of Cr3C2. The organization of both CoCrMo and Cr3C2/CoCrMo alloys consisted of epitaxial columnar crystals and homogeneous cellular crystals, and the addition of Cr3C2 reduces the number of columnar crystals. The mechanical characteristics of specimens were tested through experiments, Cr3C2/CoCrMo specimens have a hardness of 514±18 HV and an ultimate tensile strength of 1520 MPa, an increase of 27 % and 39 % respectively compared to CoCrMo specimens. Under the same load, Cr3C2/CoCrMo alloy demonstrates superior wear resistance and less wear loss than CoCrMo alloy, and the wear resistance is improved by 30%. During the SLM process, the added Cr3C2 particles melt rapidly, Cr generates a solid solution strengthening in the matrix; Cr3C2 transforms at the grain boundaries to generate M23C6-type carbides with precipitation strengthening, improving the strength and wear resistance of the alloy.