During the edible oil production process, massive amounts of by-products are generated each year that are not efficiently utilised, posing economic and environmental challenges. Under-utilised products derived from valuable oil-plants such as oil-extracted wheat germ, oil-extracted moringa seed, oil-extracted walnut and flaxseed meal will be increased, and new integration concepts will be required as soon as possible. These underutilised products can be rich sources of phenolic compounds and bioactive peptides with appropriate health-promoting properties such as anti-diabetic, antioxidant, anti-hypertensive, antiinflammatory, anticancer and antibacterial properties, according to this review. The recovery of bioactive compounds from these by-products can go a long way toward ensuring a sustainable food supply. Current challenges and requirements for recovering bioactive peptides and phenolic compounds from underutilised products derived from valuable oil-plants as well as the relationship between their biological activity and structure are discussed in this study.