In this paper, the performance of microwave photonic link is analyzed based on Taylor series expansion method. In order to improve the accuracy of theoretical analysis of microwave photonic link, this method analyzes the application range of Taylor series expansion method based on the Taylor series and the modulation coefficient. The results show that when the modulation coefficient m is in the range of 0-1.74, the average peak value calculated by Bessel function expansion method is 5-6 dB higher than the experimental data, while the average peak value calculated by Taylor series expansion method is 1-2 dB higher than the experimental data, which is closer to the theoretical calculation results.