Species of fungi that belong to the genus Trichoderma produce a variety of secondary metabolites with different valuable function including biocontrol and growth promotion activity. In this study, T. yunnanense was tested for their effect on plant diseases caused by Fusarium, Alternaria, Penicillium and Aspergillus in dual culture method. Six secondary metabolites were extracted from T. yunnanense and tested against different fungal pathogens. It was observed that secondary metabolites having Rf value 0.76 showed the highest inhibition percentage of mycelial growth and germination of pathogen followed by 0.66 and 0.53. It was also illustrated that, application of T. yunnanense after mass multiplication using different agriculture waste products such as coconut peat, rice husk, sugarcane bagasse and tamarind seeds increases the overall growth of tomato plant. These results clearly indicate that T. yunnanense may have a role in both plant defense responses and plant growth promotion activity. This is the first report of biocontrol and growth promotion activity of T. yunnanense from Bihar.