Based on the theory of linear polynomial fitting algorithm,the micro-displacement error of phase-shifter which can induce the rotation of fringes in the processing of phase shift is analyzed. A novel method for static interferogram analysis,named the virtual grating phase-shifting moiré fringe method that is based on virtual grating technology,phase-shifting interferometry and moiré technology,is introduced and analyzed. When the static interferogram with a certain spatial frequency in the experiment is processed by this method,the phase shift is introduced mathematically and controlled by the computer to avoid any phase-shifting error,so the dynamic phase could be evaluated. Some valuable experiments are carried out and the results are presented to show the feasibility of this error-analysis method. In terms of error analysis,the criterions to control the error are presented.