An windbreak aero-board apparatus disposed behind a passenger seat of an open-top vehicle for protecting a passenger on the seat from a swirling wind blast is comprised of a lower shield member transversely extending and secured to opposite sides of the vehicle body and an upper shield member transversely extending in the vehicle body which is connected to the lower shield member so as to turn up and down between an upright position in which the upper shield member stands up on top of the lower shield member and a retracted position in which the upper shield member is placed below the top of the lower shield member.