Abstract: The extrusion casting Al-20Si alloy was homogenized at 530 ℃ for different time. The effects of homogenization treatment for different time on the microstructure and wear resistance of Al-20Si alloy were studied by microscopic observation and friction wear test.The results show that there are a large number of needle-like eutectic Si phases in the microstructure of as-cast Al-20Si alloy.With the increase of homogenization time, the number of Si phases per unit area of Al-20Si alloy increase first and then decrease, and the roundness of Si phase increases first and then decreases. Si phase roundness is best in alloy homogenized for 16 h. With the increase of homogenization time, the wear resistance of Al-20Si alloy increases first and then decreases.Al-20Si alloy homogenized at 530 ℃×16 h has the best wear resistance, and its tensile strength and elongation are 158.3 MPa and 10.4%, respectively.