Purpose <p>This paper proposed a lightweight lever-type nonlinear energy sink (L-LNES) to response to the challenge of vibration reduction in weight-limited composite structures.</p> Methods <p>First, the dynamic equations of the composite laminated plate with the L-LNES are derived using the Hamilton principle and analyzed through the Galerkin truncation method. The vibration reduction performance of the L-LNES for composite laminated plates is examined using the harmonic balance method, revealing the complex dynamics of the closed detached response phenomenon. Furthermore, the analysis of optimal parameters is thoroughly discussed, clarifying the vibration control mechanism of the L-LNES through the optimization of target energy transfer using the complexification-averaging method.</p> Results <p>An experimental setup for the L-LNES vibration control is established to verify the theoretical vibration reduction effect. The experimental results indicate that the L-LNES achieves vibration reduction rates exceeding 60% by adjusting the lever ratio, with a mass ratio of 6.1%. Meanwhile, the parameter optimization results show that the maximum vibration reduction percentage and the energy dissipation rate of the L-LNES are 89.75% and 91.15% under the optimal parameters.</p> Conclusions <p>The L-LNES is effective in vibration suppression with a small attached mass. Accompanied by the disappearance of the closed detached response, the emergence of the phenomenon of strongly modulated response has a positive effect on the vibration reduction. The nonlinear relationship between the L-LNES optimal parameters is uncovered that as the lever ratio increases, both the mass ratio and damping of the L-LNES are negatively correlated with the lever ratio and decrease nonlinearly.</p>