Provided are a reflector that reflects incident light and comprises crystalline plastic in which a crystal region and an amorphous region are mixed, wherein the amorphous region includes a plurality of orientation layers comprising amorphous particles that are oriented in a predetermined direction, and a method of manufacturing the same. The reflector, which has high reflectance, is formed by extending a crystalline plastic material exhibiting a superior extensibility to extend the amorphous particles in the amorphous region in the predetermined direction so as to form a plurality of extension layers in the amorphous region. According to the present invention, since a reflector having a superior performance with a very improved reflectance can be provided due to a high diffuse reflectance by the extension layers in the amorphous region without a foaming process or an additional additive to increase the reflectance, the manufacturing process of the reflector is simplified and the manufacturing cost is reduced so that productivity can be greatly improved.