Abstract: Profit of resource provider is always uncertain because price of resource has important impact on market competitiveness. A co-reservation strategy was presented, which could be used to quantitative analysis the relationship of reservation price, resource competitiveness and profit. Based on real statistical characteristic of local tasks, the model provids the grid job QoS guarantee and local job QoS guarantee, which balances the conflict between market competitiveness and profit of resource provider by efficient price adjustment. The validity of the model and its algorithm were presented theoretically. The performance of the proposed strategy was simulated in a grid simulation system using the real task load of the practical grid system. The results show that the proposed co-reservation strategy outperforms traditional reservation strategy in terms of balancing resource load, profit rate of resource node and QoS guarantee.