In　this　paper,　an　elastic　metamaterial　beam　model　with　mechanical　and　electromechanical　resonators　is　proposed.　The　electromechanical　resonator　is　composed　of　piezoelectric　layers　and　shunt　circuit,　and　the　mechanical　resonator　is　designed　by　high-static-low-dynamic　stiffness　(HSLDS),　both　of　which　can　provide　negative　stiffness　mechanism.　Firstly,　the　fully　coupled　equations　are　established　by　using　Hamiltonian　principle.　Secondly,　under　the　assumption　of　an　infinite　number　of　resonators,　the　influence　of　resonator　parameters　on　the　bandgap　characteristics　is　analyzed.　In　addition,　the　modal　expansion　method　is　employed　to　study　the　frequency　response　function　of　a　cantilever　beam　with　a　finite　number　of　resonators　under　the　base　excitation.　The　results　show　that　the　additional　mass　ratio,　residual　stiffness　ratio　and　electromechanical　coupling　coefficient　have　great　influence　on　the　bandgap　characteristics.　Combining　the　mechanical　and　electromechanical　resonators　can　effectively　expand　the　bandgap　ranges　of　the　metamaterial　beam.　The　locally　resonant　metamaterials　with　HSLDS　and　electromechanical　resonators　designed　in　this　paper　can　obtain　better　bandgap　characteristics　and　attenuation　performance.