A safety helmet structure includes a safety helmet formed with a base portion which is located at a position adjacent to a user's one ear. The base portion is provided with an insertion groove which is provided with a threaded seat. A seat is mounted on the base portion and provided with an insertion flange that may be inserted into the insertion groove of the base portion. The seat has a receiver, and a speaker. A signal connecting cord is extended from the seat, and connected to a mobile telephone. The seat is provided with a through hole for passage of a threaded rod. The threaded rod is provided with a thread that mates with the thread of the threaded seat. A spring is mounted between the base portion and the seat for adjusting the protruding position of the seat.