A novelty Al matrix composite reinforced with Cr₃C₂ particles was prepared by an ultrasound vibration treatment-assisted casting process. The Cr₃C₂ content on the microstructure and mechanical properties of Cr₃C_2p/Al composite were researched systematically. The results indicated that Cr₃C₂ particles were effectively distributed around the grain boundary and led to a great reduction in crystalline size. The density, porosity, and Vickers hardness of the composites rose simultaneously with the increase of Cr₃C₂ content. Meanwhile, the tensile strength and yield strength increased by 104.5% and 85.7%, respectively by adding 3.0 wt. % Cr₃C₂. The fracture morphologies showed that the fracture mechanism was plastic fracture for the pure Al and gradually transformed to brittle fracture as the content of Cr₃C₂ exceeded 3.0 wt. %. Moreover, the strengthening mechanism of the composite was also discussed.