Terahertz(THz) science and technology has become a hotspot in electromagnetic field recently, in which the generation of terahertz wave is the key technology, and Photoconductive Antenna(PCA) is currently the typical approach for terahertz wave generation. The recent progresses of output coupling properties of THz wave generated by PCA are reviewed, including the output coupling efficiency, radiation patterns, as well as polarization properties. The significance of photoconductive antenna radiation characteristics research on photoconductive antenna application is discussed and prospected, which gives a guide for the research and applications of the THz wave generated by PCA.