Abstract: TRIZ is known as the theory of the solution of inventive problems, which can help R & D people solve difficulties, break the mindset, remove obstacles in product or technological innovation and get new solutions to the practical problems. In this paper, multiple solutions in the TRIZ theory, such as the root cause analysis method, conflict resolution theory, technology evolution, Su-field analysis and standard solution, functional analysis and trimming, are introduced to improve the performance of underwater acoustic ranging receiver system synchronizing with transmitter. Ten solutions are obtained and the optimal solution is determined. When the optimal solution is applied to the new system, the performance of the receiving system is expected to be greatly improved, the complexity of the system will be significantly reduced, and the reliability and maintainability of the system will be greatly improved. It is expected that the TRIZ theory can be applied in more technical fields to solve practical problems.