The invention provides a drill hole positioning device which comprises a positioning part, a guiding frame and a guiding cylinder. The positioning part is provided with a concave positioning area matched with the outer surface of a workpiece to the machined. The guiding frame is connected to the positioning part. The guiding cylinder is connected with the guiding frame in the guiding direction in a rectilinear motion mode, and is provided with an inner hole for being connected with an electric drill so that the drill bit of the electric drill can penetrate through the inner hole and extend towards the concave positioning area. The drill hole positioning device can effectively prevent the drill hole deviation caused by the sliding of the hand-operated electric drill in the process of pipeline part drilling, and the precision of a matched hole is improved.