Abstract: In order to solve the retaining rope problem of the motorized winch tail rope in construction of transmission lines in China, so as to reduce the safety risk in the operation process, a design and development scheme of hydraulic automatic take-up device for the winch and grinding tail rope is proposed in this paper. Focusing on the analysis of the rational effectiveness of the structural design and principle, design and calculation of the tail rope retraction device are calculated; and the designed active rope retraction speed is 35 m/min and the maximum tensile force is 500 N. The field test shows that the device can meet the demand of the construction site; it effectively solves the problem of leaving a rope behind the grinding mill and requiring manpower to pull when lifting heavy objects by using the motorized grinder, and provides data reference and technical support for the further mechanization of the motorized grinder.