Olive (Olea europaea L.), is widely propagated through semi-hardwood cuttings to ensure true-to-type plant production. However, root formation in some commercial cultivars remains challenging. The formation of adventitious roots (ARs) involves complex anatomical, physiological, biochemical, and molecular mechanisms in response to wounding, detachment, or stress, which are not yet well understood in olive cuttings. Hormonal signaling pathways, including auxin, ethylene, cytokinin, abscisic acid, gibberlic acid, jasmonic acid, brassinolide, and strigolactones are significant contributors to ARs formation, which auxin is a primary initiator. Hormone crosstalk further complicates this regulation, and the influence of each phytohormone through the regulation of many differently expressed genes can be either positive or negative. Endogenous phenolic compounds, which interact with auxin, also significantly influence ARs formation through their concentration and temporal changes. These compounds can act as synergists, positive contributors, or inhibitors. In addition, polyamines act as growth regulators and interact with phytohormones such that the role of exogenous putrescine has been shown to promote rooting in various olive cultivars. Carbohydrates also provide the necessary energy for gene expression and hormone signaling concerning ARs formation in plants. The role of oxidative enzymes and oxidizing agents can also be interpreted by considering the above factors. Meanwhile, new approaches such as biostimulants as well as biotechnology tools such as bacteria, and mycorrhizae fungi have been reported for root system development. Therefore, this review effectively addresses the roles of the factors above in the rhizogenesis of olive cuttings, providing insights to improve rooting efficiency in challenging cultivars.