A control device for a twin-roll continuous caster, comprising a plurality of maps, each of which teaches a relationship between a thickness of a cast strip and a roll separating force under a fixed casting speed, and teaches stable casting conditions under which bulging and surface cracks do not occur. The device detects a cast thickness and a height of the molten pool and selects an appropriate map from among the plurality of maps, by the detected height, and controls the casting conditions such that a target thickness of the cast strip is obtained under stable casting conditions by using the selected map.