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Considering that the traditional elliptical beam feed is narrow bandwidth and is difficult to fabricate, a new type of elliptical beam feed is designed in this paper. The novel feed is obtained by loading metamaterial layers on the inner wall of a pyramid horn. This method makes the beams radiated by the feed show similar elliptical shape for both the horizontal and the vertical polarization. According to the impedance matching principle, when the product of the wave impedance in horizontal and vertical polarization is equal to the product of wave impedance in vacuum, the performance of the metamaterial unit cell is optimized. By periodically loading the inner wall of the horn with the optimized unit cells, the metamaterial layer is formed and the elliptical feed horn is achieved. The elliptical feed can be used as either prime focus feed or second focus feed. For both cases, the radiation performances are verified using GRASP software. The simulation results show that in the operating frequency band of 10.95GHz-14.5 GHz, the elliptical radiations of the feed are achieved. The beamwidth ratio is between 0.9 and 1.14, and the standing wave ratio is less than 1.55. When the feed is used for a prime focus reflector, the antenna efficiency is between 65% and 75%, and the cross-polarization level is lower than -30 dB. When the feed is used for a second focus reflector, the antenna efficiency is between 61% and 72%, and the cross-polarization level is lower than -30 dB. These results verify the feasibility of the feed design.