The invention discloses a quantitative cutting device for cables and relates to the field of automation. The quantitative cutting device comprises a cable assembly; the cable assembly comprises a cable reel, a bracket and an auxiliary regulating mechanism, and the cable reel is erected on the bracket and is connected with the auxiliary regulating mechanism; a conveyor belt mechanism is arranged atone side of the cable assembly and is provided with a quantitative pushing mechanism, and a cutting mechanism for cutting cables is mounted at the tail end of the conveyor belt mechanism. The quantitative pushing mechanism realizes quantitative pushing of the cables, the cutting mechanism realizes cutting of the cables, a conveyor belt is driven to rotate by push force of the quantitative pushingmechanism completely, and thus, cost is saved, and problems of safety accidents due to fatigue, high labor load, low production efficiency and poor cutting quantity of the prior art are solved.