PURPOSE: To provide a method for controlling molten metal surface level in a mold for continuous caster, by which changing time of casting speed can further be shortened while controlling the molten metal surface level at a high accuracy without developing a hunting and to obtain a device used to this execution.

CONSTITUTION: In an FFC 2, the casting speed from a speed controller 11 and the opening degree from a hydraulic cylinder 9 are given, respectively. An opening degree correcting value ≥MVvc is calculated with the FFC 2 based on the following equation. ΔMVvc=KFF×W×Z×Kvc-n×ΔVc. Wherein, ΔMVvc: opening degree correcting value, KFF: feedforward gain to the casting speed, W: mold width, Kvc-n: molten metal supplying quantity fixed from the n-th break point approximation-opening degree characteristic gain, ΔVc: variety of the casting speed.