The present study aims to characterise the biological control agent (BCA) and plant growth-promoting fungi (PGPF) traits of four Trichodermastrains from Misiones soil. To achieve this, a dual confrontation assay was conducted, and production of β-1,3-glucanase, chitinase, and indole acetic acid (IAA) was quantified. All Trichodermastrains inhibited the growth of yerba mate root pathogens. LBM116 showed the highest β-1,3-glucanase production. LBM112, LBM120, and LBM219 produced the highest chitinase activity. LBM112, LBM116, and LBM120 displayed the highest indole acetic acid production. The BCA and PGPF indexes proved to be valuable tools for selecting LBM120 for the inoculation assay in yerba mate plants. Yerba mate plants treated with LBM120 demonstrated the highest chlorophyll content, dry weight and incidence percentage compared to the control group. Trichodermastrains from Misiones soil are promising BCA and PGPF for improving the development of yerba mate crops.