Abstarct: In order to investigate the effect of bio-fertilizers on yield and yield components of corn (Zea mays v.single cross 704) an field experiment was conducted as a split-plot factorial baxsed on completely randomized blocks in 1388. The experiment contained 12 treatment in three replications. The main plots and sub-plots contained vermicompost in two levels {application (A1) and non-application (A2)} and mycorrhiza inoculation in three levels{non-inoculated (B1), Glomus mosseae (B2), Glomus intraradise (B3)}, Nitroxin containing nitrogen stabilizer Azotobacter and Azospirillum in two levels {application (C1) and non-application (C2)}. The results indicates that using vermicompost caused significant increase in seed yield and yield components on the final harvest in comparison with non-application.Among the mycorrhiza specious, inoculation with Glomus mosseae had the most effect on leaf area and plant height and also caused a 12%, 17.3%, 21.9% increase in 100seed weight, seed dry weight and total plant weight respectively.The effect of applying both mycorrhiza specious on the investigated traits was statistically the same. By Nitroxin inoculation leaf area in plant (4691.11cm2), height (196.21 cm), 100seed weight (30.2g), seed dry weight (25.57 g/per plant) and total plant dry weight (453.46g), significantly increased in comparison with non-inoculation.The interactive of mycorrhiza inoculation and vermicompost and also Nitroxin inoculation and vermicompost on 100seed weight was significant so that applying vermicompost and Glomus mosseae (A2B2) simultaneously was the most effective component among all the treatmen components wich caused the traits to increase. Plants which received Nitroxin and vermicompost (A2C2) simultaneously had better 100seed weight, seed dry weight and total plant weight in comparison with the control treatment.