This paper presents an automatic 3-D laser measurement system of an environmental structure using the cooperation of multiple mobile robots. The robots are equipped with two types of laser sensors and measure the 3D environmental structure while moving around the environment automatically. To identify the measurement positions by the robots, Cooperative Positioning System (CPS) is utilized which is a highly precise positioning technique of co-operative multiple robots. Since the positions of the robots for 3D laser scanning are identified precisely, the 3D environmental model can be constructed without any post-processing procedure such as the ICP algorithm or manual intervention. Therefore, a fully automatic 3-D measurement system of the environmental model can be realized. This paper presents the manual and automatic planning experiments of measurement procedure using the partially measured structure of the environment. Planning and measurement experiments by three mobile robots are successfully carried out.