An input apparatus, a control apparatus, a control system, and a control method that are capable of correcting an output signal when a hand movement is input to the input apparatus and with which a user does not feel a phase delay are provided. An input apparatus includes a velocity calculation section, a filter, a control section, and a memory. The velocity calculation section calculates velocity values of a casing in X′- and Y′-axis directions based on physical amounts output from a sensor unit like acceleration values in the X′- and Y′-axis directions output from an acceleration sensor unit. The filter attenuates, by predetermined scale factors, velocity values of signals of the predetermined frequency range out of the velocity values calculated by the velocity calculation section. Since the filter dynamically attenuates the velocity values of a shake frequency range in accordance with the velocity values, a precise pointing operation with a pointer becomes possible.