A high reflectance mirror having a high reflectance in a visible-light region, being excellent in durability such as a moisture resistance, a saltwater resistance, etc. and having small dependence on incident angle (i.e., the fluctuation of the reflectance depending on an incident angle of light is little) is provided.The high reflectance mirror comprises a substrate and a silver film, a low refractive index film and a high refractive index film laminated on the substrate in this order wherein an adhesion improving film is formed on the silver film surface on the opposite side of the substrate, the extinction coefficient of the low refractive index film is at most 0.01, the extinction coefficient of the high refractive index film is at most 0.01, the adhesion improving film is an oxide film and the extinction coefficient of the adhesion improving film is at most 0.1.