Disclosed is a detection device for a power construction safety belt hanger which is a column type fall protection device. The device comprises a composite insulation rod with a locking mechanism at the lower end. The upper end portion of the composite insulation rod is provided with a hanging point or a hanging device for a safety belt. The column type fall protection device is fixed on an I-shaped equipment base through the locking mechanism. A portal frame provides force support for the equipment base. An electric hoist is mounted in the middle of a cross beam at an upper end portion of the portal frame. A groined adapter coupling attachment is disposed horizontally on cross braces in the middle of support frame bodies at the two sides of the portal frame, and the detachable I-shaped equipment base is fixed on the groined adapter coupling attachment. The I-shaped equipment base is a fixing bracket used for mounting a maintenance platform and simulating a switch blade or a switch. The detection device has the characteristics of being simple in structure, easy to use and mount and high in equipment base stability, enabling the test to be compatible with other fall protection impact tests, greatly reducing equipment manufacturing cost and so forth.