Abstract: A phase screen model based Global Navigation Satellite System (GNSS) scintillation simulation is developed for predicting the impacts of ionospheric scintillation on GNSS signals. The method consists of the phase screen generation and solution of parabolic wave equation (PWE). The 2-D realization of spatial phase fluctuation is realized by passing a normally distributed, zero-mean random sequence through a special designed filter based on the power spectral density (PSD) function. The parabolic wave equation is solved using the split step technique to compute the complex amplitude reaching the receiver antenna. It accounts for the oblique propagation of the GNSS signals and the characteristic parameters of scintillation-producing irregularities, all of which determine the strength of scintillation and could be retrieved from measurements. Ionospheric scintillation impacts on GNSS signals is simulated with the parameters for observation from low-latitude areas in China. Comparison is also conducted from various aspects with the simulated signal and that of field observation, including the amplitude variation, statistics characteristics of intensity and phase, spectral analysis of signal time sequence. It demonstrates that GNSS scintillation simulation can reproduce the scintillation impacted GNSS signals, and the outputs are consistent with the theory analysis and the field data analysis, which show the validity of the GNSS scintillation sinmulation.