In order to control of seed and root rot of cotton (Sahel cultivar) antagonistis activity of Pseudomonas flourescens and fungi Trichoderma viridae, T. harzianum were studied on Rhizoctonia solani and Pythiwn ultimum. To study antagonistis activity, cotton seeds immersed into suspensaon of antagonistic agents and then was planted in plastic pots. The precen tage of soil infection in each pot were different and the linear regression analysis indicated that infection rate inoculated soils with antagonist agents were more than free soils. The suppression effect of antagonist bacterium was more than antagonist fungi on pathogenic agents. Also antagonists were paired (on opposite) with 4 isolates of each pathoges.Significant differences (P<0.05) were observed on inhibition zone between bacterium and pathogenic agents but not antagonist fungi.