In this paper, based on the unipolar long duration lightning current wave with large frequency span, how to widen the measuring bandwidth of self-integrating Rogowski coil and how to widen the measuring range of current are studied. Aiming at the characteristics of the pulse current wave, which is characterized by the rapid change of the front part and the slow change of the tail part, a self-integrating Rogowski coil with manganese-zinc (Mn-Zn) and nickel-zinc (Ni-Zn) ferrite as the core is designed based on the analysis of the spectrum of different pulse current waves.Comparing the measured results, the following conclusions are obtained: nickel-zinc ferrite as the core, the higher the magnetic permeability, the lower the lower limit frequency of the coil, the better the low-frequency response, and the worse the response of the high-frequency part; the manganese-zinc ferrite and nickel-zinc ferrite with the same magnetic permeability Body core, the larger the saturation flux, the larger the current amplitude that the coil can accurately measure.