Caliber rolling process, useful for mass production of high precision and high strength material, was employed to process Mg-3Al-1Zn (AZ31) alloy at 250, 300, 350, 400 and 450 °C. The effects of caliber rolling temperature on the microstructure and tensile properties at room temperature were investigated at a strain rate of 1 × 10-4 s-1. The nature of stress-strain curves obtained was found to vary with the temperature employed in caliber rolling. Grain size is refined from 33 μm in mill-rolled condition to 3.6 μm upon caliber rolling at 300 °C. This condition results in ultimate tensile strength of 290 MPa and total elongation of 22% in comparison to 188 MPa and 18% respectively for mill-rolled condition. © (2014) Trans Tech Publications, Switzerland.