The invention discloses an escalator glass baseboard positioning device. The device comprises a first positioning unit used for positioning the horizontal distance between a left clamping base and a right clamping base. The first positioning unit comprises a positioning shaft and a first positioner capable of moving in the length direction of the positioning shaft. The device comprises a second positioning unit used for positioning the distance between an upper clamping base and a lower clamping base. The second positioning unit comprises a telescopic shaft. A second positioner is arranged onthe telescopic shaft. A third positioner is arranged on a glass plate. According to the escalator glass baseboard positioning device, the distance between the left clamping base and the right clampingbase can be well adjusted through the first positioning unit according to the width of an escalator and the actually demanded distance between the glass plate and a step side plate, and meanwhile, the effect that the left clamping base and the right clamping base are arranged on the two sides of the escalator in a midline symmetry mode is ensured. The distance between the upper clamping base andthe lower clamping base can be adjusted by the second positioning unit according to the length of the glass plate, and thus the glass plate can be better fixed by the clamping bases.