An elevator safety device includes: a lower beam; and an emergency stop device mounted parallel to the lower beam in order to perform an emergency stop of an elevator car, wherein the lower beam includes: a first side member; a second side member disposed opposite the first side member; a front support member configured to be coupled to and to support front portions of the first side member and the second side member; and a rear support member configured to be coupled to and to support rear portions of the first side member and the second side member.