Abstract: A novel system calibration model in fringe projection profilometry (FPP) was proposed, which does not require the connecting line between two optical center parallel to the reference plane, the optical axis of the imaging system is perpendicular to reference plane and the two axes intersect. The coefficients of the phase-to-height relationship can be deduced by using only two different height gauge blocks, which are irrelevant to the coordinate system. The maximum relative error is 0.6% among 4 measured gauge blocks. The experiments demonstrate that this calibration method is flexible and the accuracy is high.