Electrochemical conversion of oxygen-to-hydrogen peroxide (H₂O₂) through oxygen reduction (ORR) is becoming a green and effective solution to replacing conventional anthraquinone industry. Advanced carbon is currently one of the most promising catalysts for H₂O₂ electrosynthesis by a selective two-electron ORR (2e-ORR), owing to its chemical and catalytic merits. To realize better performance of 2e-ORR over advanced carbons, extensive efforts is devoted to constructing highly efficient carbon-based active sites, which requests in-depth understanding of their underlying catalytic roles. Here, an informative and critical review of recent investigations on active sites on advanced carbons for 2e-ORR is provided. Together with our recent findings, the review first highlights the promoting progress on heteroatom-doped carbons, and their direct/indirect contributions for 2e-ORR has been emphasized. Simultaneously, defect engineering of carbon scaffold is briefly demonstrated as a practical strategy for achieving outstanding H₂O₂ production. Meanwhile, the review also offers analysis on striking influence of surface modification for carbon active site. Finally, challenges and perspectives of the advanced carbon catalysts for 2e-ORR are outlined. Such reviewed fundamentals of active sites in this emerging field would shed light to future impactful progress in ORR and broader research of energy and catalysis.