A sound signal processing apparatus includes a sliding operation detecting section to which a sound signal collected by a microphone is inputted, and which determines start and end of a sliding operation by a determination process using a sliding sound signal component in the inputted sound signal, the sliding sound signal component being produced by the sliding operation on the microphone itself or its vicinity, and a control section that performs a predetermined control process that is set with respect to the sliding operation, during a period from the start to the end of the sliding operation determined by the sliding operation detecting section.