Most species of Trichoderma are antagonists to a number of fungal pathogens and because of their success in this field are widely considered as the most important fungal agent in biological control. Trichoderma species can easily be isolated from soil due to their high growth and production of condium. Also due to the formation of chlamydospores and the colonization of minerals by soil washing methods can be easily isolated. In order to isolate Trichoderma, samples were taken from different regions of Lorestan province and the samples were transferred to the laboratory and they were kept there. The samples were taken from a depth of 10 cm from the soil of the gardens and fields. Then, in a laboratory environment, the dilution series and soil cultivation methods were directly applied to the Trichoderma isolate on Elad & Chet (1983) specialized culture medium. In order to purify, mycelial tip and single spore methods were performed on a Water agar medium (WA). In order to investigate the morphological characteristics of the species, isolates were transferred to CMD medium in 12/12 light conditions and Identification of isolates based on valid keys and morphological specificity, such as the shape and size of spores, and the formation of phyalids on conidiophores and growth at different temperatures were identified. From different soil, 200 isolates, Trichoderma harzianum, T.longibrachiatum, T.breicompactum, T.asperellum, T.citrinoviride, T.atroviride, T.viride, T. aurandinaceum were isolated. T.harzianum was the most frequent with 98 isolates. T atroviride species was the least frequent among the isolated species with 10 isolates.