In the partial regions of long span roof surface especially front and corner area, wind load always present distinct characteristics of non-Gaussian. It will produce large error if Gaussian model is still adopted. On the basis of wind tunnel tests, a research was carried out on partition of Gaussian and non-Gaussian regions of wind pressure on the roof surface. Firstly, the third and fourth order statistical moments of fluctuating wind pressures are employed to obtain a description and measurement of the non-Gaussian feature. Furthermore, non-Gaussian regions on long span roofs are determined. In addition, the results of divided non-Gaussian wind pressure regions are also received by using curve fitting method based on k-s test, afterwards, the peak factor of each measuring point is given corresponding to guarantee rate 99.38 percent. Comparing the two methods above, it has been found that the results almost coincide. Non-Gaussian regions tended to be concentrated in the front, wake area and corner area near the high points. The analytic results showed that value of peak factor regulated in Chinese load codes should be improved properly and the value should be taken according to partition of regions.