A controller including a learning control unit for determining learning data based on a positional deviation between a target-position command commanding superimposed-type motion including repetitive motion and a positional fed-back variable obtained from an output portion of an electric motor; and an operation control section for controlling the electric motor based on a corrected positional deviation. The learning control unit includes a first learning section for periodically determining, based on the positional deviation, and storing, first learning data according to a first learning period; a learning-data correcting section for correcting the first learning data to eliminate an influence of a local change included in the target-position command or the positional fed-back variable and periodically arising according to a period different from the first learning period; and a positional-deviation correcting section for correcting the positional deviation by using corrected learning data.