Provided is an active acoustic control program that can reduce noise in a vehicle interior irrespective of the vehicle type, due to being installed in a device that is easily available to anyone. This active acoustic control program is downloaded using a communicator that transmits and receives data to and from a server, and this program causes a computation process device to execute a process for generating a control signal that causes a canceling sound to be outputted from a speaker provided in an interior of a vehicle in order to reduce noise in the vehicle interior. Said program is provided with an adaptive notch filter that processes a reference signal as an adaptive signal to generate a control signal, and a control filter coefficient update unit that continuously updates a filter coefficient of the adaptive notch filter so that an error signal is minimized.