The invention discloses a mater saw grooving device capable of adjusting the grooving depth. The mater saw grooving device comprises a machine body supporting seat, a depth blocking plate, a cutting depth scale label, a handle knob, a bolt, a locking nut, a locating hole and a machine head, wherein the machine body supporting seat and the depth blocking plate are assembled through a screw, the cutting depth scale label is fixedly connected to the machine body supporting seat, a boss is arranged at one end of the machine body supporting seat, a small kidney-shaped groove, a large kidney-shaped hole, a wrench and an indication plate are arranged on the depth blocking plate, a first arc and a second arc are arranged on the small kidney-shaped groove, the first arc and the second arc are both matched with the boss, the handle knob is fixedly connected with the upper end of the bolt, and the bolt, the locking nut and the locating hole are in threaded connection. The mater saw grooving device capable of adjusting the grooving depth cannot only groove but also can accurately adjust and control the grooving depth.