Abstract: The shelf support bracket includes a shelf mount, a wall mount, and a support member that together form a one-piece bracket, particularly suited for supporting shelves. The shelf mount and wall mount are each formed of a plate having an elongated groove extending from one end of the plate along a portion of the length of the plate. The support member is generally gusset-shaped, having a tongue formed along each of the edges normal to each other. the tongues and the grooves may be dovetail shaped. The ends of the mounts from which the grooves extend are mitered at complementary angles so that the mounts may be abutted normal to each other. The mounts are secured to the wall and bottom surface of a shelf, respectively, so that the shelf is installed by sliding the support member onto the wall mount and the shelf mount onto the support member.