Monte Carlo protocols to simulate the string relaxation modes are proposed according to the Hamiltonian of the molecule-string model for glass transition. The simulated relaxation times of the 1st and 2nd modes are consistent with the predictions of the string relaxation equation of the model,thus matually verifying each other. The results show the reasonableness of not only the string relaxation equation, at least the theoretical predictions of the 1st and 2nd relaxation modes, but also the proposed simulation method, and further clarify the pictures of the molecule random energy fluctuations and jumps of the molceules in the strings, as well as provide gist and clews to the study of the multi-state molecule string relaxation dynamics and the further simulation of the complex interactions between the molecule strings.