The present invention provides a measuring 
system, which comprises a surveying device installed at a known point, at least one 
photodetection device to be installed at a measuring point, and a main arithmetic device; wherein the surveying device projects by rotary 
irradiation a 
reference plane forming 
laser beam including two or more fan-shaped 
laser beams with at least one of the fan-shaped 
laser beams tilted and a distance measuring light performs 
distance measurement by receiving a reflected distance measuring light, and performs communication of the 
distance measurement data between the 
photodetection device and the main arithmetic device; wherein the 
photodetection device calculates an 
elevation angle with respect to the surveying device based on a photodetection 
signal issued by receiving the 
reference plane forming laser beam, calculates an elevation position based on the 
elevation angle and the distance to the surveying device, and performs communication of 
distance measurement data and elevation position data at least with the main arithmetic device; and wherein the main arithmetic device communicates at least with the photodetection device among the surveying device and the photodetection device, and collects and records surveying data such as distance measurement data, elevation position data, etc. for each measuring point.