PURPOSE: To produce with high yield a master disk for information storing medium which contains tracking guides and signal information pits formed with high accuracy, by forming the 1st recessing/projecting part on the surface of a substrate and then removing a part of said recessing/projecting parts to obtain the 2nd recessing/ projecting part.

CONSTITUTION: A photoresist layer 2 is formed on a substrate 1 made of glass, etc., and the laser light condensed by a lens 3 is exposed to form an exposed part 4 on the substrate. Then the part 4 is removed by developing and fixing, and Cr, etc. is vapor- deposited over the entire surface of the substrate 1. A lift-off process is applied after removing the layer 2 and Cr on the layer 2 to obtain the 1st recessing/projecting part 6. Then a chalcogenite glass layer 7A and then a metallic layer 7B of Cu, Al, etc. are vapor-deposited to form a recessing/projecting forming layer 7. Then the laser light is condensed to form a part 7C where the metal of the layer 7B is doped to the layer 7A. The layer 7 is removed by excluding the part 7C to obtain the 2nd recessing/projecting part 11. The parts 6 and 11 are used as a tracking guide and a signal information pit, respectively. In such a way, a master disk is easily produced for an optical information storing medium having high accuracy.