The invention disclosed a blast hole depth gauge and a measuring device, which belong to the technical field of blast hole measuring tools. The gauge comprises a shell, a hand holding rod, a
crank, a wire wrapping wheel disk, a measuring
rope, a hammer and a depth
display device, wherein the hand holding rod is disposed on the middle of the shell, the
crank, the wire wrapping wheel disk and the depth
display device are fixed on the shell, the depth
display device comprises an observation window, the gauge also comprises a measuring
rope pressure sensing device, the measuring
rope pressure sensing device comprises a measuring rope by-pass stationary
idler wheel, a measuring rope by-pass dynamic
idler wheel, a measuring rope
pressure sensing plate, a spring plate, a spring
plate fixation plate and a spring plate pointer, the measuring device comprises the blast hole depth gauge and a back bearing device, and the back bearing device comprises a gauge frame, a belly top device and straps. The blast hole depth gauge and the measuring device disclosed by the invention can realize precise measurement of a hole depth and a
water depth, can realize accurate positioning of a hole position, and are applicable to precise blast hole positioning in an ore area and a rock area.