To easily perform collimation calibration of laser beams with high accuracy.

In a laser optical axis collimation constituting system, for collimation adjustment, a visible laser emitting device 44 is mounted to a laser beam transmitter 34. The optical axes of laser beams emitted by the laser beam transmitter 34 and the visible laser emitting device 44 are made to become parallel with the centerline of a collimation telescope 12, and one reticle on a collimation calibration plate 20 and a reticle of the collimation telescope 12 are made to correspond to each other. By radiating visible laser beams emitted from the visible laser emitting device 44 to the other reticle on the collimation calibration plate 20, the direction of invisible laser beams emitted from the laser beam transmitter 34 and used for wireless transmission is aligned with a light receiving device for receiving the laser beams.