The tensile deformation behaviour of two recently developed aluminum alloys in the temperature range 200-500 °C is characterized in this paper. The aluminum alloys studied here are an automotive stamping grade Al-Mg-Mn alloy and an Al-Li-Cu alloy. Tensile properties at elevated temperatures were determined under different temperature-strain rate combinations. An analysis of deformation and fracture behaviour at elevated temperatures is also presented. The Al-Mg-Mn alloy and the Al-Li-Cu alloy exhibited extended ductility or mild superplasticity at elevated temperatures. Metallographic and fractographic studies revealed appreciable grain growth and cavitation at elevated temperatures. The fracture elongation of Al-Mg-Mn alloy decreased beyond 430 °C. Pronounced apparent strain hardening was observed in the case of the Al-Li-Cu alloy in the temperature range 525-550 °C at a very low strain rate. This could be due to dynamic grain growth and/or dislocation structure evolution.