The fusariosis of the tomato is a disease difficult to be controlled and it is looked for in the biocontrol an alternative. The objective of the work was to verify the action of isolates of Trichoderma harzianum on the development and protection of seedlings against tomato fusariosis. Seed treatment with three isolates and a mix of T. harzianum were used to evaluate germination, emergence and seedling development. For the controled fusariose two forms of application of the control agents were used, via seed and substrate, and for the seeds were also carried out biological and chemical treatments. It was observed that osisolates of T. harzianum did not promote dotomate germination and emergence. For the seed or substrate treatments, the lowest incidences were found in the treatment Rhodiauram + HTSR5 and the dose of 0.5g of powder (HTSR5),
