Microstructure,　texture　evolution　and　strain　hardening　behaviour　of　the　Mg-1Y　and　Mg-1Zn　(wt%)　alloys　were　investigated　under　room　temperature　compression.　Microstructural　characterization　was　performed　by　optical　microscopy,　scanning　electron　microscopy,　electron　back　scattered　diffraction　and　transmission　electron　microscopy.　The　experimental　results　show　that　Mg-1Zn　alloy　exhibits　conventional　three-stage　strain　hardening　curves,　while　Mg-1Y　alloy　exhibits　novel　six-stage　strain　hardening　curves.　For　Mg-1Y　alloy,　rare　earth　texture　leads　to　weak　tensile　twinning　activity　in　compression　and　consequently　results　in　a　moderate　evolution　to　texture.　Moreover,　inefficient　tensile　twinning　activity　and　weak　slip-twinning　interaction　give　rise　to　excellent　ductility　and　high　hardening　capacity　but　low　strain　hardening　rate.　For　Mg-1Zn　alloy,　basal　texture　leads　to　pronounced　tensile　twinning　activity　in　compression　and　consequently　results　in　rapid　evolution　to　texture.　The　intense　tensile　twinning　activity　and　strong　slip-twinning　interaction　lead　to　high　strain　hardening　rate　but　poor　ductility　and　low　hardening　capacity.