The invention discloses an anti-overturning positioning device for multi-pair finished cables, which comprises a moving support rod, a fixed support rod, a first pinch roller, a first guide wheel, a second pinch roller, a second guide wheel and a positioning mould. A first support and a guide wheel fixing plate with a through hole are positioned at two ends above the moving support rod respectively, and a cable through plate is mounted on the outer side of the guide wheel fixing plate through a connecting rod. One end of the fixed support rod is fixed to the inner middle of the guide wheel fixing plate, and a second support is vertically arranged at the other end of the fixed support rod. The first pinch roller and the first guide wheel with a groove are parallelly mounted at the inner upper end of the guide wheel fixing plate, the second pinch roller and the second guide wheel with a groove are parallelly mounted at the upper end of the second support, and a middle guide wheel with agroove is vertically mounted in the middle of the fixed support rod. The positioning mould is positioned at the upper end of the first support. Using the positioning device can effectively reduce overturning of core cables and improve production efficiency, and the anti-overturning positioning device is free of fault and maintenance, simple and easy in operation.