A control device of the wire electric-discharge machining apparatus includes a speed-ratio computing unit that calculates machining speed information related to a corner machining speed in a corner machining portion corresponding to an amount of machining in the corner machining portion, on the basis of NC data, a feedback machining-speed computing unit that calculates, as a feedback machining speed to be used for feedback control of wire electric-discharge machining, a machining speed corresponding to an inter-electrode state between a wire electrode and a workpiece measured during wire electric-discharge machining, and a multiplier that calculates a machining speed to be used for control of a machining device at a time of machining the corner machining portion, on the basis of the machining speed information and the feedback machining speed.