Abstract: Microscopic morphology observation and EDS element scanning were conducted on as-cast 6063 aluminum alloy bars before and after homogenization treatment, and the element segregation was analyzed. Through single-factor variable experiments, the steady-state and transient simulations of vehicle luggage rack 6063 profile during extrusion were conducted respectively using the finite element simulation software HyperXtrude to investigate the influence of different process parameters (bar preheating temperature, extrusion cylinder temperature, mold temperature) on the extrusion forming quality. And the flow behavior of the metal on the surface layer of the billet was analyzed. By measuring the element distribution on the surface and inside of the bar material before and after homogenization treatment, it is found that although homogenization treatment can effectively alleviate segregation, it cannot completely eliminate the segregation. As the preheating temperature of the bar material and the temperature of the extrusion cylinder increase, the quality of the extrusion molding deteriorates; however, as the temperature of the mold increases, the quality of the extrusion molding improves. The surface metal of the billet exhibits two flow patterns during the extrusion process: one part flows along the edge towards the extrusion direction, while the other part flows in the opposite direction to the extrusion and converges in front of the extrusion pad. This study provides important theoretical guidance and practical references for process optimization and quality control in the aluminum alloy extrusion industry.