People in the industry hold different opinions on supplementary protective equipotential bonding.Some arguments are analyzed and some misunderstanding is clarified in this paper:related terms are corrected according to relevant standards and literature;the specific measures and key points for the setting of supplementary protective equipotential bonding are analyzed;methods are proposed for checking supplementary protective equipotential bonding;related concepts and principles are explained in details,so as to realize appropriate application in engineering practice.