Meta-analyses demonstrate that the application of biochar is an effective practice for improving the ecosystem services of soil. Several studies have demonstrated the plant growth-promoting effects of Trichoderma spp. However, the extent of the influence of biochar and Trichoderma on microbial indicators is still poorly understood, especially in semiarid soils undergoing regenerationTo address this gap, this study evaluated the effects of biochar derived from grape stalks (B1) and grape fermentation (B2), co-applied with Trichoderma aureoviride URM 5158 (F1) and Trichoderma hamatum URM 6656 (F2), on chemical and microbial indicators in maize-cultivated soil under natural regeneration. Our findings revealed that both biochar applied in this soil changes in phosphorus, potassium, total organic carbon, microbial biomass, alkaline phosphatase, and beta-glucosidase. B1F2 increased phosphorus levels by 82 % and beta-glucosidase activity by 142 %. Our results show that B2 increased soil carbon levels by 196 % compared to the control. Soils treated with B2 exhibited a 196 % increase in total organic carbon. As for microbial biomass carbon (MBC), Trichoderma aureoviride outperformed all other treatments, resulting in a 291 % increase compared to the control. The results of this study provide evidence that biochar and Trichoderma can be used to restore the chemical and biological properties of soil.