The invention relates to a bridge rotation device and a bridge rotation construction method. The rotation device comprises a
spherical bearing, a bracket and a track, wherein the
spherical bearing is arranged at the bottom of one end of a bridge; the bracket is fixed on one end of the bridge provided with the
spherical bearing; the track is in the shape of a circular arc and takes the spherical bearing as the circle center; and a
flexible cable or a rigid member is arranged between the top end of the bracket and the bridge. In addition, the rotation device is provided with a lift
winch, the
flexible cable on the lift
winch is connected at the top end of the bracket, and the
flexible cable passes through a main sliding location element which is arranged on the track and slides along the track or the
winch to be directly installed on a main sliding platform on the track. Besides, the rotation device comprises a rotation driving device for driving the bridge to rotate additionally. The rotation device can ensure that the bridge can not swing in the rotation process, so as to enable the bridge to stably rotate, thereby saving the cost and being used repeatedly.