Workpiece inner hole diameter measuring device

The utility model discloses a device for measuring the diameter of an inner hole of a workpiece, which comprises an aperture measuring scale, a moving block, a left depth measuring scale, a right depth measuring scale and a spring, and is characterized in that the diameter of the inner hole is measured through the aperture measuring scale, and the depth of the diameter of the inner hole in the workpiece is measured through the left depth measuring scale and the right depth measuring scale; meanwhile, the maximum expansion distance between the left depth measuring scale and the right depth measuring scale also corresponds to the diameter of the inner hole, so that the maximum expansion distance can be conveniently displayed on the hole diameter measuring scale, the left depth measuring scale and the right depth measuring scale are driven to move through the moving block, and meanwhile, the left depth measuring scale and the right depth measuring scale can move up and down; the space between the left depth meas