In order to solve the problem that the edge detection cannot be realized a prior and the edge extraction efficiency is too low，a more efficient subpixel level edge detection method based on Fourier single pixel imaging is proposed. Combined with fast Fourier single pixel imaging，this method reduces the number of phase shift steps of the image algorithm，and realizes the three-step phase shift and two-step phase shift edge detection respectively on the basis of the original four-step phase shift. The improvement of the algorithm can expand the spectrum width of edge extraction under the same number of samples，so as to improve the efficiency of edge extraction. The numerical simulation results show that， compared with the four-step phase shift subpixel level edge detection，the peak signal-to-noise ratio（PSNR）increases 2.27 dB in the sampling range of 655~13 100 times under the condition of no noise，and the two-step phase shift method can obtain a higher edge extraction quality than the four-step phase shift when the noise floating ratio is lower than 0.054. The method proposed in this paper can improve the efficiency of edge extraction to a certain extent，and promote the technology crossover and application development of the single pixel imaging field and image processing direction.