The invention discloses a phase compensation method for photonic time-stretch ADC, belongs to the field of photoelectric technology, and addresses the problems of power consumption and phase distortion caused by dispersion of prior art. The method includes the following steps: (1) acquiring a stretch signal, i.e., acquiring time domain data after the stretch of the time domain; (2) conducting Fourier transformation on the time domain data of the stretch signal to obtain a frequency spectrum distribution; (3) multiplying positive frequencies and negative frequencies of the frequency spectrum distribution with corresponding phase compensation factors to obtain compensated frequency spectrums; (4) conducting reverse-Fourier transformation on the compensated frequency spectrums to obtain time a domain signal without phase deviation distortion. According to the invention, the method is intended for realizing time domain recovery without phase deviation distortion of a wideband microwave signal, and increases simulation bandwidth of a system.