In this paper, we first analyze the requirements for teaching spoken Japanese in colleges and universities, design a computer-assisted teaching system using C/S and three-layer hybrid architecture, and create a business flow diagram of the system. The second step is to conduct a technical analysis of the computer-assisted teaching system, and Bayesian theory is employed to model the complex system with multi-factor synergy. The effect of the computer-assisted system on Japanese-speaking teaching courses in colleges and universities was analyzed. The results indicated that the students dictated 4,500 words, while the lowest dictated as little as 300 words, but overall, they were more balanced. The prompt word ratio was directly proportional to the number of repetitions by observing the number of single dictations of students.