Twelve isolates of Trichoderma were isolated from soil rhizosphere of plantation crops represent different geographic areas in Egypt. These isolates were morphologically identified and the genetic relatedness of these isolates was analyzed by PCR-based Random Amplified Polymorphic DNA (RAPD) using 10 random primers. RAPD profiles showed high genetic diversity among the isolates with the formation of four distinct clusters. \nThe Antagonistic abilities of Trichoderma isolates were evaluated against Rhizoctonia solani and Pythium aphnidermatum as soil borne plant pathogens in dual culture plates. The results of antagonistic tests showed in general that these isolates are more active in inhibition growth of P. aphnidermatum than R. solani and the isolate of Trichoderma TZ2 was the most efficient isolate in inhibition growth of P. aphnidermatum and of R. solani of 78℅ and 73℅ respectively. The Trichoderma isolates TK and TM3 showed the lowest inhibition activity against P. aphnidermatum and R. solani respectively.