A pot experiment was carried out to study the effect of inoculation with single,dual and triple inoculants of N₂-fixer A. brasilense, P-solubilizer B. megaterium var.phosphaticum and the vesicular-arbuscular (VA) mycorrhizal fungus Glomus macrocarpus on growth and nutrition of maize in a calcareous soil amended with rock phosphate (0.5%) & compost (0.5%), and fertilized with low dose of N mineral fertilizer.  A significant positive effect on plant growth was obtained after inoculation of maize particularly with composed inoculant, in the presence of ½ dose of N fertilizer.  Composed inoculants significantly increased the accumulation of N, P and K in maize plants.  N₂-ase activity of maize plant roots was higher when A. brasilense and G. macrocarpus or A. brasilense, G. macrocarpus and B. megaterium var. phosphaticum were combined particularly in the presence of ¼ dose of N fertilizer.  High percentage of VA mycorrhiza colonization in maize roots was formed, indicating good ecological adaptation of the mycorrhizal fungus to the calcareous soil.  The introduced biopreparations were able to colonize actively the rhizosphere of maize.   The results obtained in this work demonstrate the potential benefit of inoculating maize plants growing in calcareous soil with a composed inoculant of N₂-fixing bacteria (NFB), P- solubilizing bacteria (PSB) and VA mycorrhiza in the presence of low dose of N fertilizer