Four biocontrol agents; Bacillus subtilis, B. amyloliquefaciens, Pseudomonas synxantha and Brevibacterium otitidis were tested individually and/or in combined mixture for suppression of Rhizoctonia solani on peanut. All tested bacteria moderately inhibited the growth of R. solani. B. amyloliquefaciens was the best for inhibiting growth. In a field experiment, combined mixture of the four tested bacteria completely suppressed incidence disease also combined mixtures of B. amyloliquefaciens and Brevibacterium otitidis or Pseudomonas synxantha and Brevibacterium otitidis gave same result. Also, dehydrogenase and nitrogenase activities, root nodulation and peanut biomass yield were determined. All tested strains increased plant parameters however, B. amyloliquefaciens and B. subtilis were the most effective ones.