A numerical analysis spherical airbag model with unilateral folds is constructed to explore the dynamic application characteristics of the folding spherical airbag. By simulating the process of airbag expansion, the dynamic characteristics of airbag expansion under different folding times and different inflating conditions are researched. The factors affecting the volume and internal pressure curves of the airbag during expansion are discussed by comparing the volume and internal pressure curves of the airbag during expansion. The results show that the more folding times on one side, the higher maximum internal pressure of the airbag. The maximum internal pressure bearing capacity of the airbag material should be considered when setting folding times of the airbag. Inflation rate and volume affects the stability of airbag expansion. Inflation rate mainly affects the initial stage of airbag expansion, while inflation volume mainly affects the free expansion stage after inflation.