A surveying system, which comprises a surveying instrument 1 which measures a distance and an angle by projecting a distance measuring light toward a target 12 and can measure a three-dimensional position data of said target and has a function to track the target, and a movable side control device 12 provided on the target side, wherein said surveying instrument has a communication means 15 capable to transmit the three-dimensional position data of the target measured by the surveying instrument to said movable side control device and a first control arithmetic unit 29 for controlling the search of the target by the surveying instrument, wherein said movable side control device has a displacement amount detecting means 38 of the target and a second control arithmetic unit 35 for calculating the displacement amount of the target based on a target detection signal from the displacement amount detecting means and for calculating a target position based on the displacement amount of the target and based on the three-dimensional position data, and in case the surveying instrument cannot track the target, the target position transmitted from the movable side control device is acquired, and the first control arithmetic unit starts searching of the target with the target position as a starting point.