The collision among robots often occurs when a multi-robot system performs the SLAM operation.However,the collision avoidance is different from the general obstacle avoidance,because the obstacles are generally not moving in the obstacle avoidance problem.In order to solve the collision avoidance problem among robots,a benefit based collision avoidance strategy for multi-robot systems is proposed.The strategy mainly focuses on improving the efficiency of multi-robot systems,and determines the order when the robots pass the intersection.Besides,the dynamic collision avoidance is considered and the algorithm of determining the order of robots' passing the intersection is given.Finally,a simulation example of robots' avoiding collision is given in order to illustrate the process of the strategy and the simulation results are analyzed.And the reasonable assumption is given for the spatial relationship between the robots and targets.