An optical information recording medium includes one or more information layers including a recording layer for recording/reproducing an information signal by irradiation with a laser light, and a seperating layer or a protective substate on which a first information layer of the information layer on the irradiation face side is formed. The seperating layer or the protective substrate having a guide groove spirally or concentrically formed on the surface, and the respective inclined planes on the inner perimeter side and the outer perimeter side of the guide groove having inclined angles .alpha. and .beta. with respect to the bottom face of the guide groove. The guide groove has one or more dissymmetric regions in the radius direction where the inclined angles .alpha. and .beta. are different. The information layer has roughly agreeing thicknesses in the inclined face portion on the inner and outer perimeter sides in the dissymmetric region.

 
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