The intensification of water pollution and the improvement of water quality standards make the efficient and economic O3-Bio⁃logical Activated Carbon (O3-BAC) drinking water advanced purification process has been more and more widely used. Based on O3-Bio⁃logical Activated Carbon process and purification mechanism, the role of coal-based activated carbon were discussed, and the key influen⁃cing factors of activated carbon for water purification were analyzed. Based on the production process of coal-based briquetted activa⁃ted carbon, the research status of the pore regulation, the development trend of coal-based activated carbon in O3-BAC water purificationprocess was discussed. Activated carbon plays an adsorption, synergistic and biological carrier role in the O3 -BAC process, which hasbetter purification effect on dissolved organic compounds (DOC), on odor and disinfection by-product (DBP). Flotation ratio, hardness,loading density and pore structure are the key indexes of activated carbon for water purification, Adjustable pore, high hardness, low flota⁃tion ratio, rough surface with high interception capacity of briquetted activated carbon, and on the scarce domestic raw material coal re⁃sources, it is expected to manufacture activated carbon products that can fully meet the stringent requirements of O3-BAC process for com⁃position performance index. Since it is still difficult to quantify and accurately regulate the pore structure of activated carbon by coal blend⁃ing technology in actual production, the mixing technology of activated carbon in O3-BAC filter is a feasible solution at present, which isworthy of further in-depth study. In addition, the existing activated carbon standard system does not yet fully cover all aspects of produc⁃tion and application. It is necessary to study and formulate standards stepping up for filter backwashing, service life of activated carbon andregeneration technical index.