To provide an optical glass, being an optical glass manufactured by a cutting method using laser light, more increases strength to make it difficult to cause breakage when external force such as impact is applied thereon, or more increases a bonding strength to a casing to more increase reliability of the product. An optical glass 100 is a plate-shaped optical glass to be bonded to a casing to cover an opening of the casing, the optical glass being made of a glass substrate 110 including: a first principal surface 110A being the side to be bonded to the casing; a second principal surface 110B being the side opposite to the first principal surface; and a cut surface cut along a reformed region R formed therein by light radiated to be focused therein, in which the reformed region R exists unevenly at the second principal surface 110B side.