Board member fastener used to rivet first board member and second board member. First and second board members each have drilled therein a different diameter of hole. First board member provides first through hole. Second board member provides second through hole. Top of first through hole of first board member is formed with stop surface that tapers toward outer diameter so that when board member fastener is punch impacted, board member fastener sinks into interior of first through hole to cut second board member and to deform, and first board member is forced by sinking stress of board member fastener and tightly pressed on second board member upon punch impact, and thus, board member fastener, first board member and second board member are deformed and fitted to each other, achieving a riveting structure that can be applied to different materials and can overcome deformation caused by heat expansion and contraction.