Laser irradiating system

A laser irradiating system, which comprises a leveling unit and a main unit provided on the leveling unit and which forms a reference plane by the laser beam being irradiated from the main unit, characterized in that the main unit comprises a rotating unit for accommodating an irradiation optical system, a first light emitting unit for emitting a first laser beam to a center of rotation of the rotating unit, and a second light emitting unit for irradiating a second laser beam of fan-like shape with spreading in parallel to an optical axis of the first light emitting unit, wherein the irradiation optical system irradiates the first laser beam from the first light emitting unit by deflecting toward a perpendicular direction and forms a first reference plane, and the second laser beam irradiated from the second light emitting unit forms a second reference plane, which perpendicularly crosses the first reference plane.