The invention discloses a constant-current output type two-way wireless power transmission system for a composite resonant network and a design method of the system. The system is formed by connecting a primary side DC power supply, a primary side choke inductance, a primary side high-frequency switching network, a primary side parallel compensation capacitor, a primary side series compensation capacitor, a loose coupling transformer, a secondary side series compensation capacitor, a secondary side parallel compensation capacitor, a secondary side high-frequency switching network, a secondary side choke inductance and a secondary side DC power supply in sequence. The system is characterized in that a novel circuit topology is provided; through carrying out parameter design on a primary side compensation mechanism, the loose coupling transformer and a secondary side compensation mechanism, the system is of a mirror symmetry structure, so that the constant-current output of the wireless power transmission system is realized while the two-way transmission of the energy is also realized. The system and the method have the beneficial effects that the complicated closed-loop control is not needed when the system is designed, the system design indexes can be met based on an AC impedance method through parameter design, the system structure is simplified, and the system stability is improved.