Abstract In this study, we explored the reversible hydrogen storage capacity of Ni functionalized C10 carbyne complex through density functional theory (DFT) and molecular dynamic (MD) calculations. ωB97X-D3/def2-TZVP and DLPNO-CCSD(T)/def2- TZVPP methods are used for the estimation of adsorption energies. NiC10 complex is observed to be more sensitive toward hydrogen adsorption compared to isolated C10 carbyne. The nH2-NiC10 complexes are stable when n≤5, and adsorption energies are in the range of −0.89 to −0.22 eV/H2 molecule while the hydrogen storage capacity is about 1.11 to 5.33 wt% for hydrogen molecule. For desorption of H2, molecular dynamic calculations are performed at ωB97X-D3 with def2-TZVP O using RCA ABMD package in which the complexes showed stability to desorption up to 2000 steps. This study illustrates the potential of nickel-doped carbyne C10 complex for the storage of hydrogen and applications in fuel cells.