This study focuses on the severe soil-borne disease problems resulting from the continuous tomato cultivation in China, with the aim of deeply studying the multi-dimensional effects of the combined application of dimethyl disulfide (DMDS) and Trichoderma on soil microecology and tomato yield. Firstly, a plate confrontation experiment was conducted in the laboratory to determine the antibacterial effect of Trichoderma afroharzianum (TAF), and the results indicated that the inhibition rate of TAF against Fusarium oxysporum, an important tomato soil-borne pathogen, was 70.8 %, which suggests TAF could be a potential biocontrol agent. Subsequently, in tomato greenhouses in Fangshan, Beijing, DMDS (60 g/m