Conventional Wireless Power Transfer (WPT) has limitation due to the contradiction between the power transfer efficiency (PTE) and power transmission distance. A novel network called Wireless Power Transfer Network (WPTN) is proposed to help overcome the limitation, and power is efficiently transferred from a transfer node to a receive node via relay nodes over a relatively long transmission distance. A novel power transfer routing optimization method for WPTN system based on the Cross Entropy (CE) method is proposed. Furthermore, an electrical load is seen as a power node in WPTN system, which has three operating statuses and are described in detail. In addition, a single power transfer route PTE mathematical model is built, and the correlation between the number of nodes, frequency and the PTE are analyzed also. Furthermore, a WPTN system with ten nodes is taken as an example, the most optimal route is selected based on the CE method according to the PTE and constraint conditions. Finally, simulation results verify the effectiveness of the proposed method, the PTE achieves an efficiency of 56.01% compared to 0.25% from a conventional two-node system.