Abstract: Background and Objective: Biofertilizers are important inputs for the productivity of olive trees. The objective of the current study was to investigate the effect of fulvic acid, effective microorganisms and effective micro-carbon on the growth and yield of two olive cultivars. Materials and Methods: Two field experiments were carried out during the two successive seasons of 2020 and 2021 on “manzanillo and picual” cultivars olive trees (Olea europaea L.) at a private orchard located in village 4 west of Miniya, Egypt. The trees were treated with six treatments as follows: (T1) control (water only), (T2) fulvic acid was added under a drip irrigation system in the 1st week of March at 100 mL per tree, (T3) effective micro-organisms was added for each tree at 100 mL, (T4) fulvic acid+K MCT® (T5) effective micro-organisms+MCT®, (T6) fulvic acid+effective micro-organisms+K MCT® where K MCT® was sprayed 3 times at the 1st week of March (full bloom), at 1st week of May (starting fruit set stage) and at the last week of July in the third stage of fruit development (70% of final fruit size) at 500 ppm. Results: All treatments improved the nutrient status (N, P and K) of the leaves, other growth parameters, yield (kg/tree) and oil percentage than the control and the promised one is the using all together where gave high values at all examined parameters. Conclusion: Olive tree yield can be improved by the addition of fulvic acid+effective micro-organisms+K MCT® under semi-arid regions in upper Egypt.