The present work was carried out at the Farm of Medicinal and Aromatic Plants Research Department, El-Kanater El- Khairiya, Horticulture Research Institute, during the two successive seasons 2011 and 2012. The present study aimed to investigate the effect of bio fertilization (active dry yeast with three concentrations 4, 6 and 8 gm/l) and some medicinal plant extracts (garlic at 50% and aloe vera with four concentrations 25, 50, 75 and 100 %) on the growth, yield of herb, oil production and chemical constituents of  basil plant Ocimum basilicum, L. The results indicated that, most treatments significantly increases plant height, number of branches, dry weight of herb as well as oil yield compared with control. The best treatment of garlic + yeast was garlic 50 % + 8 g. yeast / L, while it was the treatment of aloe 100 % for aloe treatments.