Biochar has been widely used in environmental remediation due to its high specific surface area, rich surface functional groups, stable structure, low cost, and its derivation from regenerable biomass. However, most existing studies focus on the physicochemical properties and functions of biochar, with few examining biochar releases. This paper analyzes the positive and negative effects of biochar releases in detail, lists methods to reduce soluble releases of biochar, and presents existing applications of low-release biochar. It provides useful methods and ideas for the preparation, modification, and application of low-release biochar in the future.