The present study aimed to evaluate, test and characterize potential biocontrol of endophyticrnTrichoderma isolates against coffee wilt pathogen (Gibberella xylarioides). In this study wernexamined the effect of pH and temperature on the mycelia growth and spore yield of Trichodermarnisolates in batch culture. Coffee root samples were collected from different ecological habitat ofrnKaffa zone for the isolation of endophytic Trichoderma isolates. The ability of Trichodermarnisolates to grow at pH 4.5, 6.5 and 7.5 were tested in liquid potato dextrose broth (PDB) medium.rnThe effect of volatile and non-volatile compounds produced by Trichoderma isolates on radialrngrowth of pathogenic fungi, F. xylarioides was also determined. In vitro antagonistic bioassaysrnwere performed to evaluate and determine the potentiality of Trichoderma isolates as biocontrolrnagents against F. xylarioides. The pH and temperature had significant effect on the growth andrnsporulation of Trichoderma isolates. It was observed that the optimum pH for maximum mycelialrngrowth and spore yield produced by Trichoderma isolates in batch cultures was pH 7.5 while thernoptimum temperature for mycelial growth and the maximum spore yield was produced at optimumrntemperature was 25OC. This work has revealed the important role that environmental conditionsrnplays in the mycelia growth and spore yield of Trichoderma isolates, a biocontrol agent. In in-vitrornbioassay the experimental results showed that all isolates of Trichoderma were able to inhibit therngrowth of F. xylarioides under in vitro experiment at rates ranging from 42.2 % to 69 % after 10rndays of incubation. The highest mean inhibitory effect on the growth of the test pathogen wasrnachieved by Gimbo Trichoderma isolate 05 (Gim-T05) (69%) followed by Gim-T10 (67.6%) andrnGim-05 (66.7%), while Gowata Trichoderma isolate 01 (Gow-01) isolate showed the lowestrn(42.2%) mean inhibitory effect restricting it almost completely in plates as compared to the controlrnconsisting of F. xylarioides growing alone. Gimbo Trichoderma isolate 05 (Gim-T05) producedrnzones of inhibition which is an indicative of the production of secondary metabolite(s) inhibitingrnthe mycelial growth of F. xylarioides. Thus, the use of novel isolates of Trichoderma with efficientrnantagonistic capacity against F. xylarioides is a promising alternative strategy to pesticides forrncoffee wilt disease management.