The present invention provides a rotary laser irradiating system, comprising a light emitter for emitting a laser beam, a rotator rotatably mounted on said light emitter for forming a laser reference plane by projecting and rotating the laser beam, and links for movably supporting said light emitter, wherein the links are tilted in such manner that it leans approximately toward the rotation center of said rotator, and the light emitter is movable approximately around said rotator. When the light emitter is tilted, the center of the rotator is not displaced almost at all within a predetermined range, and there is no need to compensate the position with respect to the target.