A processing apparatus using a laser beam, which comprises holding means for holding a workpiece, and laser beam application means for irradiating the workpiece, held by the holding means, with a pulsed laser beam capable of passing through the workpiece, thereby deteriorating the workpiece. The laser beam application means includes pulsed laser beam oscillation means and transmitting / focusing means for transmitting and focusing the pulsed laser beam oscillated by the pulsed laser beam oscillation means. The transmitting / focusing means focuses the pulsed laser beam, with a time difference provided, to at least two focus points displaced in the optical axis direction.