In order to realize the accurate assessment of AC contactor state, point at the uncertainty of the state parameters of AC contactor and the uncertainty of which state parameters are chosen as the evaluation factors, the grey fuzzy theory is applied to state evaluation of AC contactor. Some representative information is selected as the state variable for evaluation. The weight set of each assessment factor at different levels is composed of fuzzy part and gray part. Its gray part is determined through using AHP to calculate the evaluation mode factor weights, combined with complete information and experience of experts to determine the ash. The fuzzy relation between assessment factor and state grade is described by the membership degree to combine qualitative analysis and quantitative analysis. The incredibility of fuzzy relation is described by the pixel gray scale to establish the gray fuzzy discrimination matrix for the comprehensive assessment of AC contactor state. The experimental results show that the proposed model can objectively and effectively evaluate the status of AC contactor.