<p>Taking AZ80 magnesium alloy reinforced with Y+SiC as the research object, we investigated its squeeze casting mechanical properties through numerical simulation. Based on a simulation software platform, a reasonable squeeze casting process scheme for the specimens was determined. The solidification process and mechanical properties of the squeeze-cast samples were simulated and analyzed. The experimental results indicate that the factors influencing mechanical properties, in descending order of significance, are squeeze pressure, pouring temperature, and holding time. When the pouring temperature is 700 °C, the squeeze pressure is 100 MPa, and the holding time is 15 s, meantime the squeeze-cast AZ80 magnesium alloy achieves optimal and stable mechanical performance. Under these conditions, the tensile strength reaches 271.4 MPa, the elongation is 7.4%, and the Rockwell hardness is 98.2 HRC. Orthogonal experiments were conducted to validate the process parameters, and the results are consistent with the simulation, confirming the optimal parameter combination. A high-strength and high-toughness AZ80 magnesium matrix composite was successfully fabricated using Y+SiC reinforcement. It show that after squeeze casting, many Y + SiC particles are encapsulated within the matrix grains, thereby significantly improving the overall mechanical properties of the Y+SiC/ AZ80 magnesium matrix composite.</p>