This investigation was conducted for two successive seasons (2006 & 2007) on mature Black Monukka grapevines to disclose the effect of inoculation with arbuscular mycorrhiza (AM) and different doses of the yeast on improving quality of Black Monukka grapes. The chosen vines were ten-year-old, grown in a sandy loam soil, located at El-Khatatba, Menoufiya governorate; spaced at 2 X 2.5 meters apart and irrigated by the drip irrigation system, cane-pruned and trellised by the double "T" shape system. Eight treatments were applied as follows; control (Uninoculated vines), inoculation with arbuscular mycorrhiza (AM), inoculation with yeast (5g/vine), inoculation with yeast (10 g/vine), inoculation with yeast (15 g/vine), (AM) + (5g yeast/vine), (AM) + (10 g yeast/vine) and (AM) + (15 g yeast/vine). The results showed that dual inoculation of AM-micorrhizae and fifteen gms of yeast gave the best results in comparison with uninoculated vines. This treatment resulted in the best yield and its components as well as the best physical properties of bunches, improved the physical and chemical characteristics of berries and ensured the best vegetative growth parameters. Dynamics of wood ripening, total chlorophyll and percentages of total nitrogen, phosphorus and potassium of the leaves and total carbohydrates of the canes were also improved. With respect to microbiological activity in the rhizosphere, it was noticed that percentage of infection of AM-micorrhizae, spore numbers of AM-micorrhizae, the populations of total microorganism and yeast populations increased in the rhizosphere as a result of inoculation of AM-mycorrhyzae and yeast.