Abstract: In recent years, hydrothermal treatment of agricultural and forestry biomass waste to produce hydrochar has been a new way of solid waste recycling. Because of its excellent performance in improving soil, enhancing soil fertility, reducing greenhouse gases and repairing contaminated soil, its application in the field of agriculture and forestry environment has become a research hotspot and focus. The preparation process of hydrochar and the impacts, effects and potential mechanisms on soil physicochemical properties, greenhouse gas emissions and contaminated soil remediation during its application in the field were systematically analyzed. The problems existing in the application of hydrochar in the field were pointed out, and the future research ideas and key directions were put forward to provide reference for promoting, managing and guiding the application of hydrochar in soil environment.