Electrostatic spraying is a kind of spray painting method used to make negatively charged paint particles move in the opposite direction of the electric field by high voltage electrostatic field, and adsorb the paint particles on the surface of the workpiece. In electrostatic spraying, the spray coating thickness distribution model is a key factor affecting the coating thickness uniformity in off-line programming and trajectory planning for spray painting robots, so it has important significance for improving the spray quality and paint transfer efficiency. Therefore, a primary and fundamental issue in the trajectory planning of spray robots is how to establish an accurate coating thickness distribution model. The research progress of electrostatic spray coating thickness distribution model at home and abroad in recent years was mainly reviewed. Based on this, the problems of coating thickness distribution model were summarized and the commonly used coating thickness simulation methods were investigated at the same time: empirical model method and CFD simulation method. Spray simulation included static spray simulation and dynamic spray simulation. Euler-eulerian and Eulerian-Lagrangian methods were commonly used in static simulations, while the dynamic spray gun method and dynamic wall method were commonly used in dynamic simulation and the dynamic wall method combined with dynamic mesh was the main method of dynamic simulation. There were three common dynamic mesh models: spring smoothing model, layering model, and local remeshing model. In dynamic simulation, there were two models commonly used in the dynamic grid method: spring smoothing model combined with local remeshing model and layering model. Finally, the research on the distribution model and simulation of coating thickness is expected briefly.