The invention discloses a device for stably conveying and cutting a power cable. According to the device, a screw rod on a feeding table is sleeved with a cable frame; a pre-conveying and pre-cutting cable is located on the cable frame; the end portion of the cable stretches into a feeding pipe; the screw rod drives the cable frame to rotate so that the cable can be conveyed to a positioning and conveying mechanism which accurately positions the cable and conveys the cable to an output mechanism; the output mechanism performs clamping and positioning after an in-place locking mechanism detects the cable; meanwhile, a storage frame rotates to perform wire winding and store the cable; after the cable is wound around the storage frame for a fixed time, the cable is clamped by a clamping mechanism arranged between the positioning and conveying mechanism and the output mechanism and cut off by a cutting mechanism; and the storage frame is disassembled from a transverse screw rod, and cables of fixed length are obtained. The above structure achieves orderly conveying and winding of the cable, fixed-length cutting is achieved, the structure is reasonable, the automation degree is high, pretreatment of the cable is facilitated, then the cable is applied to required places, and the problem that the cable is difficult to cut in use and the waste problem that too many cables are used are solved.