The utility model relates to a double-reflection photon crystal optical fiber comprising a fiber core and an envelope. The envelope is arranged outside the fiber core, and the reflection rate of envelop is lower than that of the fiber core, which is composed of an inner core and an outer core. The inner core is made of solid material, and air holes constituting outer core are evenly arranged in the shape of a diamond outside the fiber core; on the whole optical fiber end surface, every three air holes are arranged in the shape of a right triangle. The air holes constituting the envelope are eight air holes arranged in the shape of a diamond or two diamonds of the same center. Optical fiber material is silicon glass material or polymer material. Air holes on the whole optical fiber end surface are arranged in the shape of a right triangle, and only the air holes at the external core area of the optical core are in the shape of a diamond. The utility model structure can be easily realized according to the current hollow regular hexahedron column piling technology for producing crystal optical fiber.