Abstarct: Plant growth-promoting rhizobacteria (PGPR) are beneficial bacteria that colonize plant roots and increased plant growth. PGPRs are able to enhance plant growth by different mechanisms such as nitrogen fixation, production of phytohormones or nutritional status of plants. In order to study of the effects of different manuring levels and bio-priming with Azospirillum and Azotobacter on yield and yield components of corn (Zea mays L.). An experiment was carried out as factorial baxsed on randomized complete block design with four replications. The investigated factors are namely, 1) manure fertilization at three levels: A1= without using, A2=5 ton per hectare and A3=10 ton per hectare. 2) Azotobacter at two levels: B1= non-inoculation, B2= inoculation and 3) Azospirillum at two levels: C1= non-inoculation and C2= inoculation. The results of this study showed that PGPR inoculants had the potential to increase maize growth during growth season and in harvest time caused enhance the yield and yield components in comparison with control. Azotobacter can be able increased all of the studied parameters (except number of seed row in ear) significantly. Azospirillum can be able to affect on all of the studied parameters (1000-seed weight and harvest index) significantly. The results showed that manure fertilizer can be able to affect on yield and yield components in comparison with control, furthermore the best yield gained in level 10 ton per hectare manure fertilizer. This results indicated that in dual inoculation of bacteria had synergistic effects. The interaction between two bacteria on grain yield, biological yield, plant height, number of seed per row, weight of ear, ear length and ear wood diameter at harvest time was significant. The results of this study indicated that application of manure fertilizer with Azotobacter significantly affected grain yield, biological yield, 1000-seed weight, weight of ear and ear length. Application of manure fertilizer with Azospirillum significantly affected grain yield, biological yield and weight of ear. It was also showed that application of manure fertilizer with Azotobacter and Azospirillum significantly affected grain yield, biological yield and plant height. Thus according to this results application of manure fertilizer and bacteria alone or simultaneous had positive effects on improvement growth characteristics and yield of corn.