Provided is a low-level bridge erection machine for erecting a high-speed railway bridge. The bridge erection machine is characterized in that the bridge erection machine comprises a low-level bridge erection machine body and a beam transporting vehicle; the low-level bridge erection machine body comprises a bridge erection machine main girder, a first landing leg which is installed at the front end of the main girder through a landing leg wheel box and a hanging system, a front-and-back hoisting mechanism which is installed on a middle track of the web part of the inner side of the main girder in a longitudinally moving mode, a second landing leg located in the middle of a main girder frame and a fourth landing leg located on the tail portion of the main girder; the upper portion of the second landing leg is hinged to supports on the two sides of the main girder frame, the fourth landing leg is hinged to the tail portion of the main girder in a mode of rotating around a connecting cross beam on the tail portion of the main girder, and a running truck is arranged at the bottom of the fourth landing leg; a third landing leg which vertically extends upwards and is used for supporting the tail portion of the main girder is installed on the upper portion of a frame of the beam transporting vehicle, and a fixing support which vertically extends downwards and is used for supporting the piggy-back rack low-level bridge erection machine body is installed on the lower portion of the front portion of the frame of the beam transporting vehicle.