A laser processing device configured to generally vertically irradiate a laser beam to a workpiece, and having a function for reducing an adverse effect due to a reflected laser beam from the workpiece. The laser processing device includes: a light condensing point moving part configured to move a focal point in an optical axis direction while irradiating the laser beam, by moving at least one of a processing head, an optical component of a light condense optical system, and a workpiece; and a light condensing point distance setting part configured to set a light condensing point distance between the light condensing point and a workpiece surface when the laser beam is started to be irradiated, wherein the light condensing point distance is set so that an amount of the reflected laser beam returned to the processing head through the optical system is not more than an allowable value.