Disclosed is an optical information recording medium having high storage reliability. The optical information recording medium is good in signal quality in high-density recording. Also disclosed are a method for recording/reproducing such an optical information recording medium, and a recording/reproducing apparatus. Specifically disclosed is an optical information recording medium which comprises at least one information layer having a recording layer and a dielectric layer in this order on a transparent substrate. The dielectric layer contains not less than 50% by molecule and not more than 98% by molecule of Zn-O, and not less than 2% by molecule and not more than 50% by molecule of one or more compounds selected from Y-O, Ce-O, Nb-O, Ta-O, Cr-O and Mo-O.