Abstract: The conductor cylinder armature is commonly used in synchronous induction coilgun. A model is developed to calculate the temperature rise of the armature based on the current filament method. The correctness of the model is verified by setting up a 3-stage synchronous induction coilgun test platform. The influence of the armature material and division setting on the temperature rise is analyzed. The result shows that the maximum temperature rise of the armature concentrates in the exterior surface of the tail, and there is a high temperature rise in the front of the armature. When the payload is adjusted to make the quality of the copper armature and the aluminum armature equal, the temperature rise of the former is higher while the influence of the temperature rise on its emission efficiency is lesser than the latter, because the temperature coefficient of resistivity of copper is less than that of aluminum. In addition, the influence of division setting on the calculation results is obvious. From the point of view of influence of the temperature rise on the emission process, the copper armature is more suitable for high-speed emission than aluminum armature.