The object of the invention is a motor vehicle door lock, particularly a backrest lock (4), on a motor vehicle seat (1). The basic construction of the motor vehicle door lock includes a locking mechanism (7, 8, 9) consisting essentially of a rotary latch (9), a ratchet pawl (7) and a blocking element (8) for the ratchet pawl (7). In addition, a drive unit (15, 16, 17) that acts on a triggering element (12) is provided. According to the invention, the drive unit (15, 16, 17) is constructed as a linear adjustment drive (15, 16, 17), which acts on the triggering element (12) so that it interacts in succession, first with the blocking element (8) and then with the ratchet pawl (7).