Two field experiments were conducted during two successive seasons to study the effect of foliar application with Phenylalanine (zero, 50 and 100 ppm) and /or nickel (zero, 50 and 100 ppm) on growth, yield and essential oil components of genoveser basil plant (Ocimum basilicum L. var. Genoveser). Application of the combined treatment (100 ppm Phenylalanine + 50 ppm nickel) resulted in the maximum values of all growth parameters, oil content and estimated yield of herb, leaves and oil. The essential oil was analyzed using a gas liquid chromatography-mass spectrometer (GC-Ms). All treatments proved that linalool was the main compound followed by 1,8 cineol, α-bergamotene, Ʈ cadinol and α-cadinol respectively. These compounds representing about 78.64% of the total oil constituents of genoveser basil. Application of 100 ppm Phenylalanine + 50 ppm nickel increased the relative percent of linalool, α-bergamotene, Ʈ cadinol α-cadinol except 1,8 cineole which was decreased by this treatment.