The present invention provides a symmetrical LCC resonance network ECPT (Electric-Field Coupled Power Transfer) system and a parameter design method thereof. The system comprises a direct current power supply, a high-frequency inversion circuit, a LC compensation network, a coupling unit formed by two pairs of coupling polar plates, a CL compensation network, a rectification filter circuit and a load RL. The LC compensation network and an equivalent capacitors Cs of coupling polar plates form a forward direction LCC resonance network, and the parameter design of the forward direction LCC resonance network ensures the constant voltage output of the forward direction LCC resonance network. The CL compensation network and the Cs form a reverse direction LCC resonance network, and the symmetrical parameter design of the reverse direction LCC resonance network is combined to ensure that the reduction voltage proportion from the excitation voltage of the coupling polar plates to the voltage of the load terminal is flexible and adjustable. The symmetrical LCC resonance network ECPT system and the parameter design method thereof can realize effects of long transmission distance and high transmission efficiency, improve system robustness, improve system power density and reduce application cost in the condition without greatly increasing system frequency and cascade compensation inductance.