An　innovative　multi-spherical　sliding　friction　isolation　(MSFI)　bearing　has　recently　been　developed.　The　novel　isolator　has　efficient　energy　dissipation　capacity　and　enough　displacement　capacity　under　strong　earthquake　excitations.　The　MSFI　bearing　is　completely　passive　devices,　yet　shows　smart　stiffness　and　smart　damping　under　external　excitation.　The　principles　of　operation　and　force-displacement　relationship　of　the　novel　isolator　are　presented　in　this　paper.　The　sliding　order　of　all　sliding　surfaces　and　force-displacement　hysteretic　relationship　are　verified　through　a　displacement-control　testing　program,　and　numerical　analysis　of　the　MSFI　bearing　under　low　cyclic　loading　is　carried　out　based　on　ABAQUS　program.　The　results　show　the　sliding　order　and　force-displacement　relationship　of　the　MSFI　bearing　derived　from　theoretical　analysis　results　and　numerical　simulation　results　are　well　agree　with　experimental　data　which　the　compression-shear　testing　of　the　MSFI　bearing　specimen　with　the　identical　curvature　radii　and　friction　coefficients.　The　adaptive　behavior　of　MSFI　bearing　permits　the　isolation　system　to　be　separately　optimized　for　multiple　levels　of　seismic　intensity　and　ground　motions.