Abstract: The hysteresis loop technique was applied to investigate the thixotropic behavior of semi-solid AlSi6Mg2 aluminum alloy slurries using a Couette type viscometer. The experimental results show that, under cyclic shear deformation, the thixotropy degree of semi-solid AlSi6Mg2 alloy increases with increasing resting time, solid fraction, maximum shear rate, and decreasing time to reach the maximum shear rate.