Under different pressure and different pulling speed conditions, the dynamic and the average friction coefficient of 6016 aluminum alloy sheets during the stamping process is tested by self-developed friction coefficient test equipment of metal sheets. A numerical model of aluminum alloy sheet expansion test is established with importing average friction coefficient to consider the friction boundary conditions. With taking forming limit diagram and critical thickness reduction rate as cracking criterion respectively, the numerical model is calculated by finite element method and the calculation results are verified experimentally. The results show that the crack initiation position and the crack morphology are more accord with experimental verification results when the critical thickness reduction rate is taken as cracking criterion, which proves the critical thickness reduction rate parameters obtained in this paper are suitable for analyzing the crack initration and propagation of aluminum alloy sheets in the stamping process.