A molding mold assembly is provided, for molding a mold substrate for an optical disc, to reduce an occurrence of burrs, etc. adversely affecting the optical disc and to improve accuracy of thickness of the optical disc made by the mold substrate. A substrate for an optical disc is provided that is capable of improving the accuracy of the thickness, as well as an optical disc with the improved accuracy of the thickness. The molding mold assembly is constructed such that a cavity for molding the mold substrate for the optical disc is configured, a stamper for transferring a hyperfine pattern onto the mold substrate is attached to the mold assembly so that a vicinal part of an innermost periphery portion of the stamper protrudes towards the cavity, and a face formed by a mold member configuring an inner peripheral portion of the mold substrate is substantially flush with an information area face on which the hyperfine pattern has been transferred.