We present an equation of dispersion characteristics for anisotropic metamaterial in this paper. In a particular direction, the dielectric constant of the material is zero at certain frequency. This property is used to produce the high-directional antenna. We develop a new metamaterial with a metallic cross-sectional structure, and simulate the radiated field of an omni-directional dipole antenna placed in the metamaterial. The radiated field is concentrated around the normal to the interface between the metamaterial and the air so that to give highly directional radiation. The gain of the antenna is 17.68 dB at 11.5 GHz, and the half power beam width is 5 degrees. The experimental results are consistent with the simulation.