The gamma distortion in fringe projection profilometry system will create obvious measurement error. A gamma correction method based on the pre-coding of projected grating is proposed to reduce the measurement error caused by the gamma distortion. By applying an appropriate pre-coding value to the projected grating, the gamma distortion effect is attenuated and the accuracy is enhanced. Experiments are carried out to verify the proposed method. The traditional phase shifting profilometry is combined with the gamma correction method. Projected sinusoidal grating of the phase shifting profilometry are modulated by the appropriate pre-coding value. Then, accuracy of measurement of the phase shifting profilometry can be effectively enhanced. Compared with the existing pre-coding gamma correction method, the proposed method is simple and effective.