A locking device for vehicle seats, in particular motor vehicle seats, has a row of detent openings and a plurality of spring-loaded bolts which are disposed one behind the other in the direction of this row. The locking bolts engage independently of one another in the detent openings. At least two of these bolts can each engage in one of the detent openings and lock the seat parts without play in both adjusting directions, in any position within the adjusting range of these parts which are to be locked. The seat parts can be continuously adjusted relative to one another. In addition to its movability enabling it to engage in one of the detent openings, each locking bolt has at least one component part which is separately movable. A flat area is provided on each bolt for play-free abutment on the delimiting surface of each detent opening and is brought into abutment with the delimiting surface without altering the depth of penetration of the bolt in the detent opening.