Abstract. In this work, friction coefficient between Polycarbonate and Aluminum was measured over the entire thermoforming temperature range by using a rotational rheometer with a specific geometry, following the B. Hegemann et al. [1] method. The effects of velocity, pressure and surface roughness were investigated. Then, numerical simulation were performed using a finite element code package for thermoforming (T-SIM®) with K-BKZ viscoelastic model. The objective of this work is to find which friction coefficient use in T-SIM simulation to be as close as possible to reality. For this, numerical simulation results for different friction coefficient were compared with experimental values to evaluate the predictive capacity. It was shown that friction coefficient is temperature dependent and rapidly increase above glass transition of polycarbonate. At room temperature, friction coefficient increases with an increase in roughness, but after glass transition, trend is reversed. Simulations with measured friction coefficients shows good agreement with experiment data.