The invention relates to a preparation device, in particular to an insulating material preparing device used for a power line. The insulating material preparing device used for the power line saves time and labor, and is high in working efficiency and short in preparation time. The insulating material preparing device used for the power line comprises a bottom plate, a first supporting column, a resin conveying mechanism, a connecting rod, a liquid adding mechanism, a second supporting column and the like. the second supporting column is fixedly connected to the other end of the top of the bottom plate, and a mixing mechanism is fixedly connected to the top of the bottom plate, is located between the first supporting column and the second supporting column and used for mixing a raw material of an insulating material; the resin conveying mechanism is mounted at the top of the first supporting column, communicates with the mixing mechanism and is used for conveying resin; and the liquidadding mechanism is mounted on one side of the second supporting column. According to the insulating material preparing device used for the power line, through mutual cooperation of the resin conveying mechanism, the liquid adding mechanism and the mixing mechanism, the effect that preparation is high in precision and efficiency is achieved.