<p>The application of biomass-derived carbon materials (e.g., biochar) into soil is considered as an attractive and sustainable strategy to enhance carbon sequestration in soil and to mitigate climate change. Our comprehensive literature analysis shows that the carbon sequestration potential of biochar in soil systems varies between 0.7 and 1.8 Gt CO₂-C_(eq)/year. Biochar with high stability and C/N ratios is effective to achieve significant carbon sequestration in soil. Furthermore, carbon sequestration is usually favourable at high biochar application rate in soil with high porosity and alkaline pH (&gt;7.5). The dominant bacterial communities enriched in the biochar-amended soil include <i>Proteobacteria</i> and <i>Acidobacteria</i>, while <i>Ascomycota</i> dominates the fungal communities. The impact of biochar amendment on soil microbial biomass and communities depends on the biochar particle size, porosity and application rate. Life cycle assessment (LCA) of biochar-amended soil reveals that biochar produced from waste biomass is found to be environmentally friendly with the acceptable level of economic feasibility in terms of large-scale applications. The recommended future research directions to seek practical applications of biochar amendment in soil include (1) development of biochar-microbe co-engineering strategies to stabilize labile carbon fractions in soil, (2) exploration of machine learning tools to optimize biochar properties for adoption of biochar treatment under region-specific soil conditions, and (3) standardization of carbon accounting methodologies to address and resolve discrepancies in LCA studies. We believe that this comprehensive review would help for development of novel biochar to achieve optimum carbon sequestration efficiency in soil and to develop practical climate change mitigation strategies.</p>