Abstract: CuSi3Mn alloy is an excellent welding material that can be used for welding dissimilar metals between copper and steel. However, it has some problems such as, a wide solidification temperature range, high viscosity, surface cracks, pits, broken rods in the production of upward continuous casting. In this paper, ProCast finite element method software was used to numerically simulate the upward continuous casting forming process of the CuSi3Mn alloy rod. The influence laws of alloy composition, die structure, casting temperature and casting speed on the depth of the mushy zone and solidification microstructure during the solidification process were systematically investigated. The results showed that decreasing the Si content, but increasing the Mn content and casting speed was beneficial to refine grain and increase the equiaxed crystal ratio. Reducing the first cold zone height and the die thickness but increasing the casting temperature could reduce the depth of the mushy zone, which was conducive to the stable growth of the solidified structure. However, the equiaxed crystal ratio decreased with the increasing of grain size. Finally, the CuSi3Mn alloy rod with qualified quality could be successfully produced, when its Si content was 2.8%‒3.0% (mass percentage) and Mn content 1.0%‒1.2% (mass percentage), with No.4 die used, the casting speed of 4‒5 mm/s and casting temperature of 1040‒1140 ℃.