Using the theory of gravitational field, we study the gravitational field induced by the node in the process of the network transmission, establish the gravitational filed equation, and define two parameters α and γ for adjusting the dependencs of transmission data on the unblocked degree of node, the transmission capacity of node and the path length. Based on the gravitational field of node, an efficient routing strategy is proposed, and the package will be transferred along the route with maximum gravitation. In order to characterize the efficiency of the method, we introduce an order parameter η to measure the throughput of the network by the critical value of phase transition from free state to jammed state, and use the node betweenness centrality B to test the transmission efficiency of network and the congestion distribution. We simulate the network transmission efficiencies under different values of α and γ. Simulation results show that compared with the traditional shortest routing strategy, our routing strategy improves the network capacity several times, and effectively balances the distribution of the betweenness centrality of nodes, and the average path length Lavg> shows a trend from ascent to descent with the increase of load amount R, and the change of the parameters α and γ nearly have no effect on the network transmission capacity, which suggests the efficiency of our routing strategy is independent of α and γ, the network capacities are approximately equal for any values of α and γ in the feasible region.