The English-Chinese machine translation system is a current research topic. This paper designs an English-Chinese comparison system based on Lagrangian search mathematical algorithm. This paper proposes a Lagrangian algorithm to describe the English short syntax and improves the English-Chinese translation algorithm. When expanding nodes, the algorithm expands on the inspiration node and expands on other nodes. The experimental results show that the improved Lagrangian search algorithm can obtain better translation results and search efficiency in the system.