The invention provides a self-check method, device and method of a high-voltage loop of a power battery. When the high-voltage loop of the power battery is initialized, a timer is started; a first voltage, which is the voltage between the common end of the power battery and a pre-charged resistor and the common end of the power battery and a high-voltage main negative relay, is obtained; when a DC main positive relay and a DC main negative relay do not exist in the high-voltage loop of the power battery, a second voltage, which is the voltage between the common end of a pre-charged relay and a high-voltage main positive relay and the common end of a load and the high-voltage main negative relay, is obtained; whether the first voltage and the second voltage satisfy a first preset self-check condition is determined; if YES, it is determined that the high-voltage loop of the power battery passes self-check; and if NO, it is determined that the high-voltage loop of the power battery fails in self-check. Self-check for the high-voltage loop of the power battery is realized, faults after closing of the high-voltage loop of the power battery are prevented, and the safety of whole automobile is further ensured.