Abstract : Fresh bun is a popular food in Vietnam and many countries around the world, with many famous dishes made from bun such as bun cha, bun ca, bun thit nuong, bun curry, etc. The research group has been developing a mini bun making machine to create convenience and food safety for the fresh bun production process in restaurants and hotels. In this paper, we have studied and simulated the number of holes on the bun extrusion mold to increase the productivity of the bun making machine. After that, we manufactured the mold according to the calculation and simulation results for experimental verification. The research results show that the bun production capacity of the machine after optimizing the number of holes on the mold increased by 20%-40% compared to the original. The research results can be applied to industrial bun production machines with large capacity today.