The utility model relates to the technical field of height adjustment, and discloses a height-adjustable mirror which comprises a supporting frame, a shell is fixedly connected to the middle of the right end of the supporting frame, a rotating rod is rotatably connected to the front end of the shell, the rear end of the rotating rod penetrates through the shell and is fixedly connected with a worm, a rotating shaft is rotatably connected to the interior of the shell, and the rotating shaft is fixedly connected with the worm. A worm gear is fixedly connected to the right side of the outer wall of the rotating shaft, the worm is in meshed connection with the worm gear, sliding grooves are formed in the left side and the right side of the interior of the shell correspondingly, and racks are slidably connected to the front walls of the interiors of the two sliding grooves correspondingly. According to the utility model, when the height of the mirror surface needs to be adjusted, the rotating rod is rotated to drive the worm, the worm drives the worm gear to rotate, the worm gear drives the two gears to rotate through the rotating shaft, the gears drive the corresponding racks to move up and down, and the racks can move up and down through the mirror frame connected with the connecting strip, so that the height of the mirror surface is adjusted; and suitable visual angles can be provided for people with different heights.