The invention provides a guide wire detecting device. According to improvement to the guide wire detecting device, the detecting device comprises a fixed hydraulic oil cylinder, a tackle, a tension loading assembly and a control cabinet which are all arranged in the same axial direction in sequence, wherein the tension loading assembly comprises a driving pulley system arranged corresponding to the tackle, a framework tower located between the driving pulley system and the tackle and provided with a driving pulley on the top, and/or an inverted-triangle moving trolley located between the framework tower and the driving pulley system, and a guide rail for the moving trolley to move in the axial direction. According to the guide wire pulley passing detecting device, an equilateral-triangle pulley passing detecting device and an inverted-triangle pulley passing detecting device can independently complete pulley passing detection, and the two systems can also complete pulley passing detection at the same time as required.