Tunnels　are　usually　located　in　highly　jointed　rock　masses　and　most　of　them　are　in　the　area　with　frequent　seismic　activities.　The　joints　have　a　great　impact　on　the　strength　and　failure　mode　of　the　rock　mass.　The　jointed　rock　mass　is　subjected　to　frequent　loading　and　unloading　under　complex　geological　and　engineering　conditions.　Shear　stiffness　is　a　key　parameter　to　reflect　the　shear　deformation　properties　of　the　discontinuities.　It　is　usually　considered　a　constant　value　in　the　traditional　calculation,　but　this　assumption　may　not　conform　to　engineering　practice　in　practical　engineering.　Loading-unloading　shear　tests　were　conducted　to　study　the　evolution　law　of　rock　joint　shear　stiffness　during　the　shearing　process.　The　rock-like　specimens　with　different　joint　roughness　coefficients　were　used　to　simulate　the　natural　rocks.　The　results　show　that　the　shear　stiffness　will　gradually　decrease　with　the　increase　of　shear　displacement.　The　shear　stiffness　of　rock　joints　increases　with　the　increase　of　joint　roughness　coefficient.　According　to　the　test　results,　a　shear　stiffness　prediction　model　related　to　shear　strain　was　derived.　The　prediction　results　were　in　close　agreement　with　the　laboratory　test　results,　and　the　error　range　was　within　12%.　Which　indicated　that　the　established　prediction　model　can　better　reproduce　the　shear　stiffness　change　behavior　of　rock　joints　in　different　shear　stages.　In　tunnel　engineering　design,　the　evolution　of　the　shear　stiffness　of　rock　joints　needs　to　be　considered.　More　accurate　results　can　be　obtained　by　inserting　the　prediction　model　into　the　numerical　simulation　programs.