Lentils (Lens culinaris) are a nutritious and popular food throughout the world. This review provides an overview of the nutritional and functional properties of lentils. Lentils have high nutritional value: high protein, high fiber, low fat, and a variety of minerals. The addition of lentils to other foods could enhance their health benefits. Additionally, there is no decrease in the amino acid content in lentils when cooked; rather, the amino acids increased and the phytic acids decreased. Lentils are generally known to have biomedical functions including antioxidative, anti-cancer, antiinflammatory, antihypertensive, and thrombolytic properties. The data presented here show that fermentation would increase the amount of bioactive substances in the beans. Therefore, fermentation techniques could be a new approach to produce lentil-based foods. They are also eco-friendly, cost-effective, and feasible processes. This review has suggested a future development of new lentil-related foods using traditional fermentation technology.