A servomotor controller capable of properly generating reference positions, by which learning control of angle based method may be applied to the periodically reciprocating motion of an object. The learning controller obtains a first positional deviation of a driven object at every predetermined sampling period of time, and the first positional deviation is converted, by a first converting part, to a second positional deviation associated with each reference position in one periodic reciprocating motion of the driven object. After a first correction amount of an immediately previous reciprocating motion of the driven object, stored in a memory, is added to the second positional deviation, the second positional deviation is stored in the memory as a renewed first correction amount. The first correction amount is converted to a second correction amount associated with the sampling period, by a second converting part.