Abstract: In order to overcome the shortcomings of the two-step phase-shift digital holography,i.e.,the need to record multiple images and the phase shift error between actual phase shift and theoretical phase shift,a new method was presented to reconstruct the real image based on a single in-line hologram.The method uses characteristics of the Hilbert transform which can achieve digital phase shift and filter the direct-current(DC)component at the same time,Hilbert transform was used twice to the recorded hologram,no DC component holograms with π/2 phase-shift and without phase shift were obtained in turn,and then the two-step phase-shift digital holography method was used to reconstruct the real image.The feasibility of the method was verified through experiments.The experiment results show that the method can well restructure the original image of the object.