I integrate the ideas of OCCAM inversion and sharp boundary inversion (SBI) to construct a new objective function for inversion by using the minimum gradient support functional and conjugate gradient inversion method to solve the optimal minimum. Through the model tests and comparisons with the related published inversion results, this method is proved accurate in determining sharp electrical interfaces based on the smoothest and stable models. It is also applied to process the field observed MT data in the regions of Guangdong Xuwen, the results indicate this method’s effect and feasibility.