It′s easier to understand in principle and faster to calculate in reconstruction by using the method of phase stepping profilometry (PSP) for three-dimensional (3-D) shape measurement. But it needs three images at least and can′t produce the absolute value of phase stepping to avoid error in practice. Virtual grating phase-shifting is proposed and it just needs one image. We first calculate or detect the base frequency f0, then use the computer to built two images by expression of cos(2πf0x) and sin(2πf0x) with π/2 phase difference. Multiply the images with original image separately, we filter the images with low pass filter and reconstruct the 3-D profile of original object by using PSP algorithm. This method reserves the advantage of PSP, solves the shortcoming of and cannot set absolute value of the phase step. In addition, the low pass filter can filter the nose of high frequency by itself, which can be used for measuring 3-D profile with non-sharp surface especially.