Maize(Zea mays L.) is one of the most important and fast developing crops in Iran. A study of maize seedling emergence, phenology, dry matter partitioning, harvest index, silage fodder and grain yield was undertaken using plant growth promoting rhizobacteria (PGPR) as biofertilizing, including four strains of Azotobacter chroococcum , Azospirillum lipoferum , A. brasilense andPseudomonas fluorescens . Late maturity single cross hybrids, SC704, SC700 and a promising single cross B73×K18 of maize were utilized in this study. Objectives of this study were to identify the most responsive hybrid and the effectiveness of PGPRs. A field experiments were conducted in 2004 and 2005. Treatments included hybrids seeds and a single inoculation by PGPRs and coinoculation by two and all PGPRs inoculants and control with no inoculation. Results revealed that application of PGPR increased final seedling emergence percentage, speed of emergence and grain filling period decreased length of seedling emergence and vegetative growth periods. At the same time PGPRs applications increased silage fodder yield and plant fresh weight and grain yield and grain yield per plant, biomass, grain dry weight and harvest index. These studies illustrated that SC700 and SC704 were the most productive hybrids for grain and fodder production respectively. The most effective PGPRs was the combination of all bacteria inoculants. Therefore, PGPRs applications could play considerable role in increasing yield and consequently development of maize cultivation.