The utility model discloses an automatic rotating system of high -speed railway seat, including the seat, the seat is connected with rotary mechanism, and rotary mechanism includes with the fixed seatpivot that links to each other of seat and drives seat pivot pivoted gear train. Rotary mechanism is connected with the rotatory slowspeed machine of drive seat, the slowspeed machine is connected with stop gear. Stop gear is including the spacing footboard of prescribing a limit to the seat position and the cam mechanism who is used for controlling locking of spacing footboard or release. Spacing footboard and cam mechanism pass through steel wire and link to each other, and the steel wire upper end links to each other with cam mechanism through last direction pretension axle, and the steelwire lower extreme leads the pretension axle under through and links to each other with spacing footboard, and automatic rotating system of high -speed railway seat still includes the controller thatis used for controlling the slowspeed machine, and the controller is connected with the position detecting element who is used for detecting the seat present position. This high -speed railway seat automatic rotary mechanism can improve staff's work efficiency, has guaranteed the punctual nature that the train dispatched a car.