Aiming at the redundancy problem in the OLSR protocol, a global minimum MPR set selection algorithm based on the isolated points is proposed. The algorithm generates a new isolated point by eliminating step by step the minimum reachable number of nodes and obtains the minimum MPR set. At the same time, the effect of the global MPR node is considered when the minimum reachable number of nodes are not unique, so as to optimize the number of MPR nodes in the whole network. Experimental results show that compared with the MPR selection algorithm based on greedy strategy, the proposed MPR selection algorithm decreases the number of MPR nodes in the whole network by 7%, reduces the network control message overhead significantly and improves the network performance.