Simplified Monte Carlo collision model of real-time traffic flow prediction is proposed. In this model, two different road cells, roads and crosses, are configured. Vehicle distribution is generated by real-time traffic flow randomly. Based on two-dimensional topology, Monte Carlo collision between road and vehicles promote time evolution of the system. Monte Carlo collision is the core of the model and traffic flow is study target. The solution of relationship equations of road and vehicles is very simple in this model to speed up the computing. In addition, parameters can be corrected and configured at any time in the process of time evolution. Experimental results show that the model has the advantages of real-time, visual interface, easy configuration, and can be corrected by real-time feedback. The model can not only simulate and predict macroscopic data, such as flow, velocity distribution, but also follow the track of each vehicle in detail. So, the model can be used in researching both macroscopic and microscopic characteristics of vehicle movement.