In this paper, the influence of ageing and solution treatment on the low cycle fatigue behavior of a rolled AZ80 magnesium alloy sheet was investigated at constant total strain amplitudes between 0.003 and 0.01. It was observed that fatigue life of the alloy sheet at as-rolled, ageing and solution treatment conditions can be described well by Coffin-Manson and Basquin’s equations. The fatigue parameters follow the two equations were evaluated. With increasing total strain amplitude, the fatigue life of the three conditions decreased. At the lowest total strain amplitude of 0.003, the fatigue life of the as-rolled alloy sheet was the biggest. However, at the highest total strain amplitude of 0.01, the fatigue life of solution treated alloy sheet was the biggest, and that of the ageing treated alloy sheet was the shortest.