Magnesium alloy sheets are usually obtained by complex processing cycles including hot rolling operations. Temperature of the final stage of rolling strongly affects the microstructure and, consequently, the hot formability of the sheets. In this framework, the present work aims at investigating the effect of the rolling temperature on the hot formability of the innovative magnesium alloy ZAM100. To this purpose, two different rolling temperatures were used and hot formability was investigated by tensile tests performed in extended ranges of temperature and strain rate. The flow curves were analyzed in order to obtain constitutive models of hot formability.