The high gain offset reflector antennas for dual polarizations terahertz application are proposed. The two reflector antennas are made of silicon carbide material and thermally stable carbon fiber-reinforced plastic respectively. The electroforming technology is used to make the high precision corrugated horn. Several mechanical and electrical tests procedures were done to verify the antenna specifications. Special efforts was made to find a reasonable and quick method to measure the large antenna patterns based on exact optical test, the results using this method are comparable to that of the near field test. The side lobe level of the silicon single polarization reflector is about -32dB,while the dual polarizations patterns of carbon fiber-reinforced plastic reflector antenna have side lobes level of -24dB and -26dB.
