The nanoscale strategy is represented to further improve the rate performance of (Co0.2Cr0.2Fe0.2Mn0.2Ni0.2)3O4 high-entropy oxide (HEO) as anode material for lithium-ion batteries. Herein, spinel-structured (Co0.2Cr0.2Fe0.2Mn0.2Ni0.2)3O4 HEO nanocrystalline powder was successfully synthesized by hydro-thermal synthesis using metal nitrate as metal source, urea as precipitant and dodecyl trimethyl ammonium bromide (DTAB) as surfactant. The research shows that by introducing surfactant DTAB in the hydrothermal process, the as-synthesized (Co0.2Cr0.2Fe0.2Mn0.2Ni0.2)3O4 HEO possesses smaller crystalline size, higher uniform dispersion, larger specific surface area and more uniform pore distribution than that without adding surfactant. This unique structural feature makes the as-synthesized electrode material have pronounced pseudo-capacitive behavior, which greatly improves the reversible specific capacity and rate performance of LIBs. The surfactant-induced electrode exhibited a higher initial specific capacity (1308 mA·h/g), significantly enhanced initial coulomb efficiency (82.5%), higher reversible capacity of 1263 mA·h/g at 0.2 A/g after 25 cycles, and outstanding rate performance accompanied with excellent cycling stability (more than eighth the reversible specific capacity of 1053 mA·h/g at 3 A/g after 150 cycles).