Sandglass extrusion is an ultrafine grain size method. Due to the repetitive and multiple extrusions, large strain can be accumulated and ultrafine grain size can be obtained. Some factors can affect the experimental results of sandglass extrusion, such as extrusion ratio, number of extrusion, extrusion temperature, friction and free space in mould cavity etc. These factors have different effects on material microstructures, properties and defects. In this paper, the effects of extrusion ratio and friction on material microstructures during sandglass extrusion process have been discussed and theory analysis and experimental results have been reported.