In order to evaluate the effects of seed priming with bio fertilizers on germination percentages, vigour and viability of maize (Zea mays L.) seeds in CRD having four replications in post-graduation department Laboratory of Genetics and Plant Breeding department, Sam Higginbottom Institute of Agriculture, Technology & Sciences, Allahabad, during 2015-2016 to assess the effects of bio fertilizers in three durations on maize and identify the best durations of priming on maize seeds with bio priming treatments T₁ (unsoaked seeds with (control), T₂ [soaked seeds with Trichoderma (1% solution for 14 hours)], T₃ [soaked seeds with Trichoderma (1% solution for 18 hours)] and T₄ [soaked seeds with Trichoderma (1% solution for 22 hours)], T₅ [soaked seeds with Rhizobium (1% solution for 22 hours)], T₆ [soaked seeds with Rhizobium (1% solution for 22 hours)], T₇ [soaked seeds with Rhizobium (1% solution for 22 hours)] on seed germination and vigour of maize. All treatments significantly affected on germination percentage, vigor index, seedling dry weight and seedling length of maize seeds. It is concluded that, Rhizobium (1% solution for 14 hours) shown the excelsior result on all observed characters of maize.