The　effects　of　starting　texture　on　he　flow　curves,　and　microstructure　and　texture　evolutions　of　AZ31　(Mg-3Al-1Zn-0.3Mn　in　wt.%)　alloy　during　uniaxial　compression　at　room　temperature　have　been　investigated　by　experiments　and　simulations.　Two　kinds　of　cylindrical　compression　samples　were　cut　from　the　AZ31　extruded　rod:　one　was　cut　with　the　compression　direction　parallel　to　the　extruded　direction　(ED),　and　the　other　was　cut　with　the　compression　axis　perpendicular　to　the　ED.　The　samples　were　termed　as　C//ED　sample　and　C　perpendicular　to　ED　sample,　respectively.　The　results　indicate　that　the　general　characteristics　of　flow　curves　and　texture　evolutions　in　both　C　perpendicular　to　ED　and　C//ED　samples　during　compression　can　be　well　explained　by　the　relative　activities　of　deformation　mechanisms,　which　show　a　strong　orientation　dependence　on　the　initial　textures　and　the　current　texture.　A　significant　yield　behavior　can　be　induced　by　(10-12)　twinning　at　the　starting　deformation,　and　the　lower　yield　stress　in　C　perpendicular　to　ED　sample　can　be　enhanced　by　the　high　activity　of　basal　＜　a　＞　slip.　The　work　hardening　behavior　is　related　to　the　activities　of　basal　slip,　pyramidal　＜　c+a　＞　slip,　{10-12}　twinning,　as　well　as　{10-11}　twinning.　However,　the　activity　of　prismatic　＜　a　＞　slip　is　insensitive　to　the　starting　texture,　and　mostly　negligible　in　all　samples.