An engagement assembly, a drawer, and a refrigerator having same. The engagement assembly comprises a first engagement part matching the drawer and a second engagement part matching a refrigerator body; one of the first and second engagement parts is a gear, and the other one is a rack; the rack has a tooth surface that allows the gear to travel; the rack comprises a main rack and an extension rack; when the drawer is in a closed state, the tooth surface has a first stroke length; when the drawer is in an opening process, the extension rack moves to a travel path of the gear so that the tooth surface has a second stroke length; when the drawer is in a closing process, the extension rack is reset; the first stroke length is smaller than the second stroke length. The length of the tooth surface increases in the opening process.