The invention provides a laser surveying device, which comprises a light emitting unit for emitting a pulsed distance measuring light, a photodetection unit for receiving a reflected pulsed distance measuring light and a control arithmetic unit for controlling the light emitting unit and for calculating a distance to an object to be measured based on a photodetection signal from the photodetection unit, wherein the light emitting unit has a pump laser source for emitting a pump laser beam, a spot diameter changing means for changing a spot diameter of the pump laser beam, and an optical cavity for emitting the pump laser beam entering via the spot diameter changing means as the pulsed distance measuring light.