The invention provides a grounding protection method and system based on a centralized new energy grid connection mode. Wiring modes and related grounding modes of grid connection primary systems of awind field and a photovoltaic power station are determined, and protection tripping or line selection tripping is determined in combination with a specific grounding capacitance current value; and according to the grounding modes of the wind field and the photovoltaic power station, corresponding over-current protection and zero-sequence over-current protection schemes are configured, and fault sequence network analysis is carried out by adopting a symmetric component method to further determine the protection tripping scheme. Tripping and shunt tripping strategies determined by the determined protection scheme make special requirements for guaranteeing rapid fault removal, avoiding overvoltage and the like; and the needs of two-party protection and safe and stable operation are met at the same time on the premise that the selection is unified with a power system.