A track-type sex aid includes a track having an outer periphery and an inner periphery opposite to the outer periphery. The track includes a plurality of protrusions protruding beyond the outer periphery of the track. An annular transmission device includes first and second wheels rotatably mounted in a space defined by the inner periphery of the track. The first wheel includes a shaft directly or indirectly coupled to a driving shaft of a power output mechanism of the annular transmission device, with the first wheel directly or indirectly driving the track.
