The present study was carried out to determine the antibacterial efficacy of crude extracts of trichoderma spp. fungi isolated from mangrove rhizosphere soil. Four different strains of trichoderma spp. were isolated and identified from marine mangrove rhizosphere soil. Crude extracts of these fungi were prepared. The antibacterial efficacy was determined by agar disc diffusion method against three different ba cterial strains viz., Pseudomonas aeruginosa (ATCC 27853), Escherichia coli (ATCC 25922), and Staphylococcus aureus (ATCC 25923) according to Kirby-Bauer disc diffusion method. Good inhibitory activity was observed in the crude extracts of Trichoderma harzianum(1), Trichoderma viridae followed by Trichoderma harzianum(2) and Trichoderma inhamatum. All the Trichoderma spp. inhibit Gram positive bacteria Staphylococcus aureus followed by the Gram negative bacteria E.coli and minimum inhibition was noted in Pseudomonas aeruginosa.The secondary metabolites of the marine mangrove fungi belonging to Trichoderma spp. can be used as a potential antibacterial agent in the increasing scenario of antibiotic drug resistance.