Provided is a servo controller that can prevent an unnecessary cut from being generated during oscillation machining. A servo controller which controls a machine tool 10 that turns a workpiece W by cooperative operation of a plurality of axes includes: an oscillation command generating unit 23 that generates an oscillation command for causing the workpiece W and the tool 11 to relatively oscillate; a deviation deducting unit 31, 241 that applies the oscillation command to a position deviation based on a moving command for causing the workpiece W and the tool 11 to relatively move, and deducts a steady-state position deviation; and a learning control unit 27 that calculates a compensation amount from a position deviation based on the moving command after deducting the steady-state position deviation.