The present application relates to an opening and closing mechanism and a train having the same. The opening and closing mechanism comprise a driving device, a locking device and a support arm; the driving device is connected to the locking device to drive the locking device to rotate; a first end of the locking device is rotatably mounted on a baseplate; a sliding groove in which a second end of the locking device is slidably located is formed on the support arm; a first end of the support arm is rotatably mounted on the baseplate; a second end of the support arm is connected to a fairing; the driving device drives the locking device to rotate, the locking device drives the support arm to rotate by the sliding groove, so that the support arm opens or closes the fairing.