A surveying system comprising a surveying instrument and a target having a pole and a prism which is provided on an axis of the pole, wherein the surveying instrument is configured to scan the distance measuring light with an optical center of the prism as a center by a circular scanning in a state where the prism is tracked, to calculate point cloud data of two points at which the pole intersects with the circular scanning, the axis of the pole and a tilt angle of the axis of the pole, a straight line on the pole which intersects with the circular scanning at two points, three-dimensional coordinates of two intersection points of the straight line and the circular scanning, and three-dimensional coordinates of the optical center of the prism, and to calculate three-dimensional coordinates of a measuring point based on the calculation result.