A method of producing a nozzle plate for use in an ink jet head includes the steps of (a) stretching a predetermined number of resin lines, each having a cross section corresponding in shape to each nozzle hole to be formed in an ink jet head, in the same arrangement as that of nozzle holes to be formed in the ink jet head, (b) plating the peripheral surface of each of the resin lines with a metal, while maintaining the arrangement of the resin lines, (c) forming a nozzle substrate so as to include the resin lines therein with the metal used in the plating of the resin lines, (d) slicing the nozzle substrate, and (e) removing the resin lines from the sliced nozzle substrate, thereby forming the nozzle plate. In the above method, the resin lines can be removed from the nozzle substrate, and then the nozzle substrate can be sliced so as to form the nozzle plate.