PURPOSE: To provide the apparatus for producing an optical master disk which prevents nonuniform diffusion between the inner and outer peripheries of a developer at the time of a development process and can produce the optical master disk without unequal development.

CONSTITUTION: A photoresist 4 is applied on the surface of a glass substrate 1 and a latent image is formed on this photoresist 4 by irradiating the resist with a light beam and is then developed, by which the optical master disk 5 is produced. A 1st arm nozzle 12 formed with a 1st nozzle hole 11 for perpendicularly discharging the developer is disposed in the position corresponding to the rotating center part of the optical master disk 5 of such apparatus for producing the optical master disk. A 2nd arm nozzle 14 formed with many 2nd nozzle holes 13 for perpendicularly discharging the developer is disposed in the position corresponding to the entire surface of the information recording region of the optical master disk 5.