The utility model discloses a slide rail type stair supporting structure, relates to the technical field of slide rail type stair supporting, and solves the problems that the position of a supporting rod of a stair is inclined, the whole stair cannot be vertically stored, and a stair main body is easy to move through arranged pulleys, so that the use of the stair is unsafe. Comprising a first step, a plurality of second steps, a plurality of third steps and a sliding rail, the sliding rail is fixedly installed on a wall, a sliding block is fixedly installed on the left side of the first step, the sliding block is in sliding connection with the sliding rail through the first step, the bottom of the third step is attached to the ground, and the second steps are multiple in number. The stair body comprises a first step and a second step which are arranged between the first step and the third step, supporting columns are symmetrically and fixedly installed at the bottom of the first step and the bottom of the second step, and through cooperation between the arranged supporting columns and moving grooves, when the stair body is stored, the third step can be pushed to the left end, and the stair body can be conveniently stored.