The present invention relates to an antenna based on a metamaterial and a method for generating an operating wavelength of a metamaterial panel. The antenna comprises a radiation source, and a metamaterial panel capable of converging an electromagnetic wave and operating at a first wavelength. The metamaterial panel is adapted to convert the electromagnetic wave radiated from the radiation source into a plane wave and to enable the antenna to simultaneously operate at a second wavelength and a third wavelength which are smaller than the first wavelength and are different multiples of the first wavelength. The present invention further provides a method for generating an operating wavelength of a metamaterial panel for use in the aforesaid antenna, which comprises: acquiring a numerical value m 3 /m 2 that is within a preset error range relative to a ratio » 3 /» 2 of a third wavelength » 3 to a second wavelength » 2 ; calculating a lowest common multiple m 1 of m 2 and m 3 ; and generating the operating wavelength » 1 of the metamaterial panel, which is represented as » 1 =» 2 (m 1 /m 2 ) or » 1 =» 3 (m 1 /m 3 ). By designing the operating wavelength of the metamaterial panel, the antenna is able to operate at different wavelengths simultaneously; and the electromagnetic wave from the radiation source can be converted into a plane wave. These improve the convergence performance and reduce the volume and size of the antenna.