[Objective] Tomato wilt is a kind of destructive soil-borne disease caused by Ralstonia solanacearum. In controlling the disease, rhizosphere probiotic play an important role. They reduce pathogen density and dull disease dynamics via resource competition and competitive exclusion. Their effective colonization in the rhizosphere is the precondition of their wilt controlling effect. As a porous material with adsorptive properties, biochar is used as a promising strategy to improve soil structure and fertility. Moreover, biochar has a great potential to inhibit soil-borne diseases, by transferring root exudates off rhizosphere and providing shelter for probiotics. To improve biocontrol efficiency of the probiotics, it is proposed that biochar is used as a carrier to improve their colonization in rhizosphere.[Method] In this study, wilt controlling effect of the application of biochar and probiotics in combination was evaluated and mechanisms underlying the potential were explored. To the end, a pot experiment was conducted to test three different kinds of biochar (derived from maize straw, pine wood and rice husk, separately) applied together with probiotic Bacillus amyloliquefaciens T-5 in controlling tomato bacterial wilt. And then an in-lab experiment was carried out too to measure efficiencies of the biochars adsorbing of pathogens and tomato root exudates in vitro. In the end, resource competition and direct toxin production of Bacillus amyloliquefaciens T-5 and their effects on pathogens were determined with simulated root exudates.[Result] Among the three kinds of biochar, the one derived from wood biochar is the highest in specific surface area (SSA) and absorption capacity, reaching up to 395.88 mm² and 116.4 mg·g^-1, respectively. The pot experiment showed that the application of biochar, regardless of kind, significantly reduced the incidence of bacterial wilt and pathogen density in rhizosphere. Wood biochar performed the best. When applied alone it decreased the incidence of bacterial wilt by 60.56%, and when applied in combination with probiotic Bacillus amyloliquefaciens T-5, it reduced pathogen density by about 97.42%, while increasing probiotic colonization by about 5.71 times. In exploring mechanisms of such potentials, it was found that 1) Biochar effectively adsorbed pathogen R. solanacearum, and wood biochar was the highest in adsorption capacity, reaching up to 90.00%, and fixing the adsorbed R. solanacearum by 94.66%; 2) Biochars absorbed root exudates, which were used by probiotic T-5 as carbon source for growth, thus inhibiting the growth of R. solanacearum.[Conclusion] As a carrier of probiotics, biochar, once applied together with probiotics can significantly decrease incidence of bacterial wilt by adsorbing root exudates probiotics relay as nutrient resources for growth and restricting the mobile ability of pathogen. The findings in this paper explain the mechanism of combined application of biochar and biocontrol bacteria controlling soil-borne tomato bacterial wilt and may serve as a theoretical basis for developing an environment-friendly, high efficiency and stable biocontrol strategy.