Abstract: The invention discloses a hook coupling comprising a principal hook body and two blocking members disposed thereon to block any object inserted into the principal hook body. The hook coupling can make the inserted object (such as shoulder belts) to be very conveniently inserted into the hook coupling. In addition, after the shoulder belts are inserted, one blocking member can compress the shoulder belts, and the other blocking member can completely seal the clearance for inserting the shoulder belts, which result in the shoulder belts being not slid out from the hook coupling.