A grounding apparatus includes a current detector configured to detect a current flowing in the ground line, a fuse inserted in series in a part of the around line and configured to melt when the current flowing in the ground line exceeds the first protection setting value, not destroying the current detector, and then exceeds the first protection setting value, causing a complete grounding fault, and a determination device configured to give an open command to the circuit breaker when the current detected by the current detector exceeds the first protection setting value of the circuit breaker.