The invention provides an excitation surge current recognition method based on negative sequence components and harmonic characteristics thereof.The method comprises the steps that fundamental components of negative sequence current and secondary harmonic components of the fundamental components are obtained from self-variable difference current or current on the power source side; positive sequence components of current fundamental waves are calculated according to three-phase current sampling values; the relative content of the negative sequence components and the relative content of negative sequence secondary harmonic components are calculated; whether the current is excitation surge current or not is judged according to the relative content of the negative sequence components and the relative content of the negative sequence secondary harmonic components.