Abstract: Based on the good neutron absorption property of B₄C and the moderated neutron property of carbon fiber (CF), CF-B₄C mixed-reinforced 6061Al matrix composites with different CF contents were prepared by vacuum hot pressing sintering method. The microstructure and mechanical properties of the composites were analyzed. After hot rolling with large deformation, the B₄C particles are distributed evenly without large area of particle aggregation, but a small amount of B₄C particles and CF are brittle. When the deformation reaches 60%, the tensile strength of the material can reach (265±3) MPa. Compared with the tensile strength of 6061Al alloy, the tensile strength values of CF-B₄C/Al composites with different thicknesses increase by 80% and 112% respectively. With the increase of CF content, the strength and elongation of CF-B₄C/Al composites decrease. When the content of CF reaches 5wt%, the main reason of fracture is the aggregation of fibers and the arrangement of fibers along the fracture direction.