SEAT ROTATING DEVICE

This seat rotating device is a seat rotating device that rotates a seat body between a seating position where the seat body faces front of a vehicle and a getting-on and -off position where the seat body faces an opening of a door of the vehicle. The seat rotating device includes a base plate fixed to a floor side of the vehicle, a turn frame arranged above the base plate and fixed to a lower surface of the seat body so as not to rotate relatively to the seat body, and a coupling unit that couples the base plate and the turn frame to each other such that the turn frame is rotatable with respect to the base plate between the seating position and the getting-on and -off position. The coupling unit includes a turn link and a drive mechanism fixed to a lower surface side of the turn link.