The invention discloses a water diversion device and method for a stream scenic area. The water diversion device is provided with a first water diversion canal and a second water diversion canal in the positions, on the two sides of the stream flowing direction, below the ground correspondingly, water pipes are fixedly arranged in the first water diversion canal and the second water diversion canal correspondingly, one ends of the water pipes communicate with the first water diversion canal and the second water diversion canal correspondingly, the other ends of the water pipes are connected with water outlet devices correspondingly, and water outlets of the water outlet devices stretch out of the ground above the first water diversion canal and the second water diversion canal. According to the water diversion device, part of stream water is intercepted and stored, drought of nearby land is prevented, even if in the drought period, dry land is changed into wetland through arrangement of the water diversion canals, meanwhile, through the water diversion method, the dry land can be changed into the wetland without large mechanical equipment, water resources are efficiently utilized,and plants are prevented from being withered in an arid season.