The utility model belongs to the technical field of rope pulleys of mine underground frames, in particular to a track gauge locating rope support pulley device of a mine underground rail conveying system which solves the problem that the current rope support pulley can not adapt to the current coal mine safety requirements and previous various vehicle requirements. The track gauge locating rope support pulley device of the mine underground rail conveying system includes a rolling body and track connecting boards at the two ends of a idler wheel shaft which can be arranged at the two sides and can be pressed at the bottom of the track; the rolling body is arranged on the idler wheel shaft through a bearing; and the track connecting boards at the two sides are connected by a stud. The track gauge locating rope support pulley device of the mine underground rail conveying system has the beneficial effects as follows: 1, the track gauge locating rope support pulley device of the mine underground rail conveying system has a simple structure and is convenient to be manufactured; 2, the track gauge locating rope support pulley device of the mine underground rail conveying system has flexible rotation, small resistance and strong adaptability; moreover, the key point is that the track gauge locating rope support pulley device of the mine underground rail conveying system can play the role of locating track gauges and can be used in various mine conveying systems; and 3, the track gauge locating rope support pulley device of the mine underground rail conveying system is convenient to be overhauled and dismounted, and is convenient for underground installation and operation.