This study aimed to investigate the impact of different types of free amino acids (proline, glutamic acid, and GABA), applied either individually or in combination, on the vegetative growth and yield of nine-year-old Manzanillo olive trees over two consecutive seasons (2021 and 2022) in a private orchard located along the Cairo-Alexandria desert road, Egypt (approximately 64 km from Cairo). The findings revealed that applying a mixture of free amino acids at a rate of 50 ppm positively influenced vegetative growth, flowering, fruit physical properties, and yield, with no significant differences compared to foliar application of 50 ppm glutamic acid alone. Additionally, the combined amino acid treatment enhanced the olive trees' resistance to salt stress by increasing total amino acid content in the leaves while reducing carbohydrate content.