The invention relates to a height detection device. The height detection device comprises a detection platform, a locating mechanism and a detection mechanism, wherein the detection mechanism comprises a base and at least one detection unit; each detection unit comprises a stand column, a detection rod, a bolt and a locating rod; one end of the stand column is connected with the base, and the other end is connected with the detection rod; a first end of the locating rod is connected with the base; the detection rod is provided with a bolt hole used for holding the bolt; the bolt hole is matched with the bolt; the side face of the head of the bolt is provided with an L-shaped gap; the distance from a second end of the locating rod to the side face of the bolt and the distance from the second end of the locating rod to the vertical face of the L-shaped gap are extreme values of the height; and the width of the L-shaped gap is the tolerance. The height detection device disclosed by the invention has the advantages of simple structure, and convenience in operation. The detection speed is improved; the accuracy of the detection result is ensured; and the detection cost is lowered.