The work aims to prepare single component sulfur dioxide adsorbent for storage microenvironment of weapons and equipment. Hydrogen peroxide was used to modify the surface of activated carbon. The porous structure andthe change of surface chemical property of modified activated carbon were investigated and the adsorption performance for sulfur dioxide was also studied. Activated carbon had micropores and mesopores. After surface modification, the specific surface area increased and the average pore diameter decreased. Hydrogen peroxide reacted with activated carbon, resulting in etching, which generated nano-scale pore structure on the surface of activated carbon and reduced the order degree of carbon microcrystalline on the surface of activated carbon. At the same time, hydrogen peroxide reacted with activated carbon to play an oxidation role, which improved the content of oxygen elements and oxygen-containing functional groups on the surface of activated carbon. The activated carbon modified by 20% hydrogen peroxide possessed optimal adsorption capacity (up to 154.15 mg/g), about 5 times as much as that of unmodified activated carbon. The activated carbon with surface modified by hydrogen peroxide generates nano-scale pores and improves the oxygen-containing functional groups. Under the synergistic effect of nano-scale pores and oxygen-containing functional groups, the adsorption performance of activated carbon for SO2 is significantly improved, which has good application prospects in equipment.