Three plant growth promoting rhizobacterial (PGPR) strains, PF1, FP7 and PB2, were tested alone and in combinations for suppression of rice sheath blight disease and promotion of plant growth under glasshouse and field conditions. The mixture of PGPR strains significantly reduced the sheath blight incidence when applied as either bacterial suspension through seed, root, foliar and soil application in glasshouse conditions, or as talc-based formulation under field conditions, compared to the respective individual strains. The average mean of disease reduction was 29.2% for single strains and 45.1% for mixtures. In addition to disease suppression, treatment with mixture of PGPR strains promoted plant growth in terms of increased plant height and number of tillers, and ultimately grain yield. The average increases in yield for single strains were 17.7%, and 25.9% in case of mixture. Mixture of three PGPR strains reduced disease and promoted growth to a level equivalent to two strain mixtures. Though seed treatment of either single strain or strain mixtures alone could reduce the disease, subsequent application to root, leaves or soil further reduced the disease and enhanced the plant growth. The mixture consisting of PF1 plus FP7 was the most effective in reducing the disease and in promoting plant growth and grain yield.