The invention discloses a DG grid-connected electric system high acceptance protection method, which comprises the following steps: when a line has fault, carrying out corresponding protection actions according to whether a grid-connected DG system side grid-connection line is provided with longitudinal differential protection; when the grid-connected DG system side grid-connection line is provided with the longitudinal differential protection, and the line has fault, carrying out line protection action to trip off a line system side circuit breaker, and intertrip off a grid-connection line switch; and when the grid-connected DG system side grid-connection line is not provided with the longitudinal differential protection, and the line has fault, carrying out line protection action to trip off the line system side circuit breaker, and carrying out main transformer high standby zero-sequence overvoltage protection to trip off a transformer high-voltage side switch and intertrip off the DG grid-connection line switch. The DG grid-connected electric system high acceptance protection method is good in flexibility and high in acceptance, can ensure safe and reliable operation of the system, and can ensure benefit of DG service providers to the largest degree.