With the continuous progresses of microwave technology, it is urgent to improve the frequency stability and phase noise index of microwave signal source. Optoelectronic oscillator has attracted wide attention because of its extremely low phase noise and good frequency expansibility. However, the sideband of the output signal is greatly increased by the long fiber inside the optoelectronic oscillator. The method to solve the contradiction between single-mode output and phase noise has become a hot topic in the field of optoelectronic oscillator. Parity-time-symmetry method can greatly optimize the sideband suppression of the output signal on the premise of ensuring the phase noise of the output signal. Based on the description and analysis of the working principle and characteristics of parity-time-symmetric optoelectronic oscillator, the structure and schemes of parity-time-symmetric optoelectronic oscillator designed by domestic and foreign research teams are summarized, and the basic principles and performance indicators of various schemes are analyzed and introduced. And the future development directions of parity-time-symmetric optoelectronic oscillator technology are discussed.