Abstract: A display lifting device includes: a body; an adjusting unit having big and small wheels coaxially disposed on the body, a shaft fixed to the body, and a rock arm pivotally fixed to the shaft and having first and second arms; a spring having one end fixed to the body; a first rope member wound on the small wheel and having two ends connected to the first arm and the other end of the spring, respectively; and a second rope member wound on the small and big wheels and having one end connected to the second arm, and a sliding unit for carrying a display such that the display is movable between a first position and a second position. Since the sum of torques produced on the first and second arms is kept equal to zero, the display can stop at any position between the first and second positions.