The invention relates to a crystal heat dissipation structure for suppressing temperature drift of an electrooptical modulator, and a manufacturing method thereof. The heat dissipation of the electrooptical modulator is improved by using the excellent axial thermal conductivity of carbon nanotubes, and meanwhile, by using the excellent light transmittance and electrical conductivity of graphene, electric charges are transferred by using multiple layers of graphene films via conducting resin to suppress the pyroelectric effect of the crystal of the electrooptical modulator, so that the temperature drift caused by the pyroelectric effect of the electrooptical modulator is greatly improved, the use and maintenance cost and frequency of equipment and device are greatly reduced, and the long-term working stability of the device is improved.