The fringe period number selection of the phase measurement profilometry is mainly based on the experiences at present,which is difficult to achieve the best solution and hardly to be applied. A quantitative selection method of fringe period number based on error model for phase measurement profilometry is proposed. Firstly,the phase error model is established according to the error source analysis of phase measurement profilometry,and then the maximum phase error is calculated by the phase error model. Secondly,the constraint equation of the fringe period numbers is derived by the constraint relationship between the maximum phase error and the phase unwrapping algorithm. Finally,according to the relationship between the maximum phase error and the constraint equation of fringe period numbers,the optimal number of sinusoidal fringe periods is obtained. The experimental results show that the standard deviation of the best plane fitting result of the standard flat plate using the number of fringe cycles selected by proposed method is 0.03mm,which is 44.4% lower than the traditional method. The method proposed in this paper can effectively improve the measurement accuracy of phase measurement profilometry.