A method for manufacturing a nozzle includes a step to change a spot diameter of a laser beam on a plate in which an orifice hole is formed. A device for manufacturing a nozzle includes a laser beam generating device for generating a laser beam, a work head comprising a lens to focus the laser beam on a plate, a driving device to move the work head upward and downward, a position detecting device for sending a signal indicating a position of the work head, and a controlling device for controlling an amount of the laser beam to be applied according to the signal from the position detecting device. The device for manufacturing a nozzle of the present invention changes the spot diameter of the laser beam on the plate. Therefore, the time period for forming an orifice hole in the nozzle can be shortened.