The present invention relates to a tunable dispersion and dispersion slope compensator based on an optical fiber grating in an optical communication system. The compensator includes: a first disk having a ring shape, wherein the first disk is configured to rotate; a second disk installed at an inner space of the first disk, wherein the second disk is configured not to rotate; a metal plate configured to bend as the first disk rotates; and an optical fiber grating adhered to the metal plate, wherein the optical fiber grating has different strains according to positions when the metal plate rotates.