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The (Ti + B4C) / AA7075 composite powder with 5 wt.% and B4C ceramic particles (3 wt.%, 5 wt.%, 10 wt.%) was prepared by high-energy ball grinding, and several groups of additive samples were prepared by laser melting deposition technology (Laser Melting Deposition, LMD). The influence of titanium elements and different mass fractions B4C ceramic powder on the microscopic organization and mechanical properties of the composite materials was studied. The results show that the addition of spherical pure titanium powder and B4C ceramic particles can effectively solve the stoma and cracking problems of 7075 aluminum alloy during LMD molding process. When the mass fraction of B4C was 3 wt.%, the average microhardness and tensile strength of the composite were 141.65 HV 0.2 and 336.93 MPa, respectively, which were 41.5 % and 68.4 % higher than 100.07 HV 0.2 and 200.05 MPa of the deposited 7075 aluminum alloy. Later, with the increase of B4C mass score from 3 wt.% to 10 wt.%, the tensile strength of the sample gradually decreased, but the wear resistance gradually increased, the average friction coefficient decreased from 0.83 to 0.78, and the wear form changed from adhesive wear to peeling wear.