A laser machining device with a proximity-warning function in relation to a workpiece being machined includes a laser element and a position feedback unit. The laser element includes a laser head for emitting a focused laser beam and a movable member for moving the laser head. The position feedback unit is positioned on the movable member and connected to an alerting circuit. When an elastic contacting member in the position feedback unit is compressed because the distance between the laser head and the workpiece is less than a minimum permitted distance the alerting circuit issues an alert.