The fungus Fusarium oxysporum is a soil plant pathogen that attack cultures causing losses in Brazilian crop production. Trichoderma harzianum is a filamentous fungus able to antagonize fungal plant pathogen. This fungus is able to suppress growth of plant pathogens and this control involves the production of proteins and secondary metabolites with antifungal activities, such as fungal cell wall degrading enzymes (proteinases, chitinases and b-1,3-glucanases) and antibiotics. In the present work, 15 T. harzianum isolates from Cerrado soil were tested to the ability of inhibit and suppress F. oxysporum growth and to produce antifungal enzymes. All isolates inhibited F. oxysporum growth with inhibition values ranging from 4,9 to 34%. Major inhibition values were obtained for ALL-24 (34%), ALL-18 (29%), ALL- 49 (27%), ALL-16 (24%) and ALL-21 (24%). In vivo assays of confront culture showed that, with the exception of ALL- 47 and ALL- 49, all isolates growing on the F. oxysporum mycelium with maximal growth after 96 h (growth area from 55 to 58 cm²). For ALL-24 and ALL-49 a cleared interaction zone was detected and the growth area was lower than for the others isolates (49 cm²). Moreover, F. oxysporum growth was suppressed in the presence of 13 T. harzianum isolates (ALL-05, ALL-08, ALL-16, ALL-18, ALL-19, ALL-21, ALL-22, ALL24, ALL-28, ALL-38 and ALL-43). All isolates were able to grow on liquid medium containing F. oxysporum mycelium as unique carbon source. All isolates produced b-1,3-glucanase activity, being major values obtained for ALL-20, ALL-24, ALL-19 e ALL-42 with U.mL⁻¹ values of: 0,32, 0,27, 0,26 e 0,19. Chitinolytic activities were also detected for all isolates without significant differences, increased activity was detected for ALL-47 (0,38 U.mL⁻¹). Alkaline proteolytic activity was detected for five isolates ALL-05, ALL-18, ALL-28, ALL-42 and ALL-43 with U.mL⁻¹ values of: 0,18, 0,14, 0,35, 0,49 and 0,47. These results showed that T. harzianum isolates obtained from Cerrado soil have antagonistic activity toward F. oxysporum and are able to produce antifungal enzymes, indicating your potential use as a model in order to understand the interaction T. harzianum-phytopathogenic fungus and to the development of biotechnological products with biocontrol and antifungal activities that could be useful for the control of fungal diseases in Brazil agriculture.