The invention relates to a material hardness detection instrument, and in particular relates to a portable digital display hardness measuring device. The portable digital display hardness measuring device mainly comprises a pressure application and indentation depth measurement device consisting of a hand wheel, a rotary encoder and a micrometer screw thread pair, and further comprises a supporting seat, a force-measuring device, a pressure head, an electronic circuit board and a display, wherein the supporting seat is provided with the rotary encoder, a micrometer nut is arranged in a hole of the supporting seat, the front surface of the supporting seat is provided with a digital display, and the side surface of the supporting seat is provided with the electronic circuit board; a micrometric screw rod is arranged in the micrometer nut; a rotating shaft of the rotary encoder is connected with the micrometric screw rod and rotates along with the micrometric screw rod; the upper end of the micrometric screw rod is connected with the hand wheel, the lower end of the micrometric screw rod is connected with the force-measuring device; the lower end of the force-measuring device is connected with the pressure head; and the hand wheel, the micrometric screw rod, the force-measuring device and the pressure head are connected to each other and are concentric, and move with rotation of the hand wheel (11) in the axial direction. The portable digital display hardness measuring device is simple in structure, convenient to read, easy to operate and high in precision, and can be fixed on metal parts through a fixing device and is used for quickly detecting hardness of large parts on site.