The physicochemical properties and the microbial communities structure of soil, as critical components of the growth substrate for pepper, significantly influence the photosynthetic characteristics, accumulation of secondary metabolites, and fruit quality of pepper. Given that soil heavy metal contamination and low fertility utilization efficiency have become key environmental constraints to pepper sustainable production, this paper systematically reviewed the predominant issues and current status of pepper cultivation areas in China. It reviews research progress on the remediation efficacy of biochar and its composites in pepper-growing soils, comparatively elucidates the passivation effects of heterologous biochars, such as lignin-based and straw-based variants, on typical heavy metals including Cd, Cr, Pb, and also evaluates different biochar's roles in reconfiguring rhizosphere pH buffer systems, enhancing soil organic matter content, and improving microbial properties. Future research should prioritize long-term studies across diverse chili-growing soils to establish optimization models encompassing feedstock, processing techniques, and application parameters, and a multidimensional evaluation framework spanning molecular binding mechanisms to field-scale validation should be developed, in order to enable the rational and efficient utilization of biochar for soil amelioration in pepper cultivation, which will provide both theoretical foundations and technical paradigms for the green transformation of the pepper industry.