Abstract: A tire is a very complex structure made from rubber and fiber-rubber composite materials. During its use, a delamination crack growth often occurs, which obviously affects its durability and life. A new crack growth model between layers in composite structures is presented in the paper. The crack growth model, Irwin's virtual crack close technique and finite element analysis method were together used in simulating numerically the growth process of the delamination crack between layers in a tire structure. The results show that the crack growth model proposed in the present paper can more really reveal the complexity of the growth process of the delamination crack between layers in a complex composite structure.