To provide a laminated body for an optical isolator having small deterioration of an extinction ratio in the plane of a light transmission surface even when polarization glass base materials are affixed, and to provide a method for manufacturing the same and an optical isolator.

The method for manufacturing the laminated body for the optical isolator which manufactures a laminated body by affixing polarization glass base materials in both sides of the light transmission surface of a Faraday element made of a bismuth-substituted iron garnet crystal through an adhesion layer includes: previously examining the tops and the bottoms in extending directions of the polarization glass base materials when the polarization glass base materials are prepared; and affixing the polarization glass base materials so that each of the polarization axes of the polarization glass base materials are arranged at a predetermined rotation angle position, by regarding a state in which the examined tops and bottoms in the extending directions of the polarization glass base materials as a reference.