Abstract: Biochar, rich in carbon, and loose and porous structure, possesses strong adsorption and decomposition resistance capabilities. Its application in agriculture provides an effective utilization way for large amounts of straw resources, and its intrinsic physical properties are conducive to soil amendment, reducing chemical fertilizer input, enhancing soil’s carbon sequestration capacity, and decreasing greenhouse gas emissions. However, the direct use of biochar as fertilizer is limited in agriculture due to its low nutrient content resulting in high transportation and storage costs, and the possible dust pollution during application. In recent years, many researches focused on developing soil amelioration agents and controlled-release fertilizers using biochar as a carrier or a specific functional component. And some biochar-based products showed satisfactory effects on improving soil structure and nutrient utilization efficiency, and alleviating soil constraints and enhancing crop growth conditions. This paper reviews the main types and preparation processes of biochar-based products, and their performance in soil improvement and fertilization, highlighting their remarkable effects on improving soil quality, crop yield, and environmental protection. Future efforts are proposed therefrom, including research and development of new materials and technology, modification of testing standards and evaluation system, demonstration and promotion of biochar-based products, and to the long-term effect on ecological environment.