The deep exploration of adsorption preferential specific structural properties of waste biomass‐derived activated carbon(AC) adsorbent is significant but challenged in the light of the synthetic control. This work optimizes chemical activation routine of waste bagasse‐derived AC to fabricate high‐performance adsorbent. The resultant optimal AC affords outstanding structural properties (SBET=2832.2 m2 g−1, SLang=5478.3 m2 g−1, Vtotal=1.93 cm3 g−1). The pre‐carbonization method (using high‐temperature calcination or hydrothermal) and the implanting approach of KOH (impregnation or grinding method) were rationally tuned, and the corresponding effect on structural properties of AC and their adsorption capacity for volatile organic compounds(VOCs) were carefully studied for the first time. The obtained optimal BC‐1 adsorbent showed the highest adsorption capacity (1604.5 mg g−1 and 1679.5 mg g−1) of benzene and toluene, which is nearly 1.73 folds enhancement compared to others derived from comparative routes. This adsorption property is far superior to that of industrial AC. Meanwhile, the adsorption capacity and adsorption behavior were further demonstrated to be directly determined by the total pore volume and Langmuir surface area of the adsorbent through correlating adsorption properties with structural characters. Besides, we demonstrated the superior adsorption selectivity of C6H6/H2O(g) (61.22) and C7H8/H2O(g) (189.33) over BC‐1 under humid conditions predicted by the DIH (difference of the isosteric heats) equation.