This invention provides a nanodisk, which can be formed of a wide variety of materials and has a high level of application, and a method for manufacturing the same. The nanodisk comprises fundamental units formed of two-molecule block copolymers arranged in series in a main chain direction, the fundamental units having been aggregated in a plane direction. The nanodisk has a thickness of 1 nm to 100 nm, a diameter of 10 nm to 5 μm, and an aspect ratio of not less than 1. Since the thickness of the nanodisk is not more than 100 nm, the nanodisk is transparent to light in a visible region. Further, when a metal element is held on the crosslinked structure part, the nanodisk can be utilized as a nanodisk having magnetic properties and electroconductive properties, or a nanodisk having catalytic activity and a high refractive index. Thus, the nanodisk can be applied to a wide variety of fields such as fine particle/powder technology, colloid surface science, electronic materials, and optical materials.