In order to evaluate the effect of inoculated bacteria: Azospirillum lipoferum, Pseudomonas putida and Azotobacter chroococcum on yield and yield components of corn cultivars SC-704 an experiment factorial under randomized complete block design with 4 replications was carried out in Astara, 2009. Seed treatments include inoculation with each of the bacteria as a single triple, double, triple and non-inoculated (control), respectively. The results showed that application of plant growth promoting rhizobacteria increased plant height, grain yield, grain weight, biological yield and all characters was significant between the bacteria at (p&lt;0/05). Also, the results revealed that increasing the number of bacterial inoculation average yield and yield components increased as the highest yield in the three inoculation treatments Azotobacter, Pseudomonas and Azospirillum to rate 13281 kg ha-1 and test it reliable to attendance control to rate 7853 kg ha-1 obtained and the other relationship. Inoculation treatments showed a lot of difference.