Material extrusion additive manufacturing (ME-AM) builds 3D models by extruding materials through a nozzle layer by layer. As the development of materials, an increasing demand of the high-temperature extrusion has emerged in additive manufacturing (AM). While the smooth and stable extrusion process at high temperature relies heavily on the nozzle, the optimization study on the metal nozzle is reported in this work. From current brass and steel nozzles, two optimized nozzles (a steel nozzle with brass embedded and a steel nozzle with brass encircled) have been designed and the thermal conductivity has been studied by simulation analysis. Then the thermal deformation of designed nozzles and traditional nozzles have been investigated at the temperature of 410°C. Conducting the extrusion and printing tests, the extrusion performance of the proposed nozzles has been compared to that of traditional nozzles. The results indicate that the proposed nozzles lead to the better thermal distribution as well as the stronger resistance to thermal deformation compared to the traditional brass nozzle. The designed steel nozzle with brass encircled shows the excellent extrusion performance and printing performance.