Control device for a stopper-rod to regulate the outflow of liquid metal through a calibrated hole of a pouring receptacle comprising motor means, suitable to operate lifting and lowering means (2) of the stopper (4) by means of first driving means (7) and second driving means (14, 14′), the latter being suitable to convert a rotating motion into a translational motion, wherein the second driving means are flexible longitudinal elements and are fixed at a first end thereof to lifting and lowering means and a second end thereof to an anchor element (9), integral with the first means.