Using molecular dynamics simulations, we investigated the reusable performance of the nanofluidic energy absorption system (NEAS) to dissipate the impact energy created by a drop hammer (simulated by a carbon plate with an initial velocity and mass). The effects of nanopore flexibility and surface roughness on the reusable performance of NEAS are also considered. The results clearly shown that NEAS can only convert the mechanical energy into the solid–liquid interfacial energy (i.e., store it in the system) in the loading stage; the stored interfacial energy is gradually released and finally dissipated as heat by the solid–liquid interaction in the unloading stage. Therefore, the unloading response of NEAS decides whether or not the system can be reused for energy absorption, which is sensitive to the loading condition. Although NEAS behaves as a one-time used energy absorption material under quasi-static loading condition, it can be reused under dynamic loading condition. In addition, the nanopore surface roughness also affects the unloading behavior of NEAS. To the best of our knowledge, this is the first time to theoretically validate the reusable performance of NEAS.