Abstract: Compared with traditional substrates, biochar has attracted more and more attention in ecological treatment processes due to its developed pore structure, abundant surface functional groups and significant economic advantages. Based on the analysis of VOS viewer software, this study systematically reviewed the application progress of biochar in ecological treatment process and the new combination process coupled with other technologies in the past ten years. The removal efficiency of biochar on conventional pollutants, heavy metals and emerging contaminants in ecological treatment processes such as constructed wetlands, biofilters and ecological ditches was analyzed. Compared with the control group, the removal rates of chemical oxygen demand, total nitrogen and total phosphorus by biochar increased by more than 10%, among which the strengthening effect on total nitrogen was the most prominent, while the removal rates of different heavy metals increased by 6.11%~22.7%. The mechanism of biochar-based materials in ecological treatment process and the key directions of future research in this field are discussed in depth, aiming to provide theoretical reference for the optimization and promotion of ecological treatment process.