In order to eliminate the influence of the phase-shifting error on the quality of reconstructed image in digital holography, single phase-shifting digital holography is studied. Based on the statistic property of the phase distribution of the diffraction field in recorded plane, an effective method for eliminating the phase-shifting error is presented, in which the unknown initial phase-shifting values can be calculated directly from the holograms, and the summation of the intensity bit errors of the holograms is taken as an evaluation function for an iterative algorithm to find the actual exact phase-shifting value. The feasibility and validity of this method is demonstrated by computer simulation and the reconstructed image.