Root rot incited by Rhizoctonia solani is one the major diseases of pea. As there are no long term management strategies for this soil borne pathogens therefore, the study was carried out to determine the effect of pH on the antagonistic activity of fungal and bacterial isolates (Th3 and Th5 (Trichoderma harzianum), An1 (Aspergillus niger), Po3 (Penicillium oxalicum) and PS1, PS2 and PS5 (Flourescent Pseudomonas) against Rhizoctonia solani at four different pH levels (5.0, 6.0, 7.0 and 8.0). All the seven indigenous fungal and bacterial isolates evaluated for their antagonistic potential against root-rot pathogen, significantly retarded the radial growth of Rhizoctonia solani in comparison to control at four different pH levels (5.0, 6.0, 7.0 and 8.0).The observations of the study revealed that all bio agents significantly inhibited the growth of the Rhizoctonia solani . Similarly, Trichoderma species had significant effects on the number and size of sclerotia. The pH range of 6.0-8.0 were found optimum for Trichoderma spp. while Flourescent Pseudomonas shows best antagonistic activity at pH 7.0. As far as the effect of pH levels is concerned, all the promising fungal and bacterial isolates caused maximum growth inhibition of test pathogens at pH 6.0 to 7.0.