A　multi-degree-of-freedom　device　is　proposed,　which　can　achieve　efficient　vibration　reduction　as　the　main　objective　and　energy　harvesting　as　the　secondary　purpose.　The　device　comprises　a　multiscale　nonlinear　vibration　absorber　(NVA)　and　piezoelectric　components.　Energy　conversion　and　energy　measurement　methods　are　used　to　evaluate　the　device　performance　from　multiple　perspectives.　Research　has　shown　that　this　device　can　efficiently　transfer　transient　energy　from　the　main　structure　and　convert　a　portion　of　transient　energy　into　electrical　energy.　Main　resonance　and　higher-order　resonance　are　the　main　reasons　for　efficient　energy　transfer.　The　device　can　maintain　high　vibration　reduction　performance　even　when　the　excitation　amplitude　changes　over　a　large　range.　Compared　with　the　single　structures　with　and　without　precompression,　the　multiscale　NVA-piezoelectric　device　offers　significant　vibration　reduction　advantages.　In　addition,　there　are　significant　differences　in　the　parameter　settings　of　the　two　substructures　for　vibration　reduction　and　energy　harvesting.