To solve the problems of too long time of pathfinding and collision and blocking during movement in real-time strategy games, a combined improved flow field pathfinding algorithm was proposed. Firstly, the red-black tree was used to store data to improve the speed of data access. Secondly, by using the penalty function, the calculation of the integration field cost was simplified through transforming the nonlinear partial differential equation problem into a linear unconstrained problem. Finally, a pre-adjacency node was introduced to generate the flow direction. Compared with the flow field pathfinding algorithm without improvement, the improved algorithm has the path calculation time reduced by 20%, and the average moving time is stable at 20 s. Experimental results show that the improved flow field pathfinding algorithm can effectively shorten the pathfinding time, increase the moving speed of Agents and improve the level of game artificial intelligence in real-time strategy games.