The invention provides a circuit protection method, a protection circuit and a circuit protection device. The current change rate of a protected circuit is detected in real time, and if the current change rate is larger than the first preset current change rate, it proves that a suddenly-increased over-current may be generated in the protected circuit; the change rate of the second current can becalculated in a time-delay mode, and a protection action is performed on the protected circuit according to the value of the second current change rate; and if the first current change rate detectedin real time is not larger than the first preset current change rate, whether the protection action needs to be executed or not is determined by calculating the sampling power of a sampling circuit inthe protected circuit, so that the situation that the protected current cannot work normally due to over-current is avoided, whether over-current exists or not is determined through a two-layer judgment mechanism, and the accuracy of the over-current protection scheme is improved.