Nineteen Trichoderma isolates, collected from different locations in Bangladesh, were characterised through phenotypic, biochemical and molecular means. Besides, they were assessed for their antifungal action in vitro. The isolates were divided into three groups: T. asperellum, T. virens and T. harzianum. A dual culture assay and a culture filtrate assay against 6 phytopathogens revealed that 9 of the 19 isolates showed significant antifungal activities. The isolate T. harzianum TR05 showed the highest inhibition against Fusarium oxysporum, Rhizoctonia solani, Fusarium circinatum and Phomopsis vexans, followed by T. asperellum TR08 and T. virens TR06. TR08 had the highest inhibition against Sclerotium rolfsii and Pythium aphanidermatum, followed by TR05 and TR06. These findings were in agreement with their activities of extracellular hydrolytic enzymes, including chitinase, β-1,3-glucanase, and proteinase. Our results suggest that isolates TR05, TR06 and TR08 have the potential to be effective biocontrol agents against the phytopathogenic fungi.