Lactic acid bacteria (LAB) fermentation significantly enhances the nutritional, functional, and sensory properties of plant-based products. This review highlights the role of LAB in transforming plant-based materials, including by-products, into valuable functional foods. LAB can hydrolyze complex molecules into smaller, more bioavailable compounds, such as amino acids, vitamins, and organic acids, improving the flavor, texture, and health benefits of fermented products. They also produce bacteriocins and other antimicrobial compounds, enhancing the safety and shelf-life of plant-based products. LAB fermentation can increase the levels of phenolic compounds, vitamins, and antioxidants, which contribute to the functional properties of plant-based foods. Additionally, LAB can reduce the bitterness and undesirable flavors in plant-based materials, making them more palatable. The review emphasizes the importance of LAB in improving the nutritional value and health benefits of plant-based products, while also addressing the challenges in their application. The study also discusses the potential of LAB in promoting health and disease prevention through the production of functional compounds. Overall, LAB fermentation offers a promising approach for developing high-nutrient, functional plant-based products with enhanced sensory and health benefits.Lactic acid bacteria (LAB) fermentation significantly enhances the nutritional, functional, and sensory properties of plant-based products. This review highlights the role of LAB in transforming plant-based materials, including by-products, into valuable functional foods. LAB can hydrolyze complex molecules into smaller, more bioavailable compounds, such as amino acids, vitamins, and organic acids, improving the flavor, texture, and health benefits of fermented products. They also produce bacteriocins and other antimicrobial compounds, enhancing the safety and shelf-life of plant-based products. LAB fermentation can increase the levels of phenolic compounds, vitamins, and antioxidants, which contribute to the functional properties of plant-based foods. Additionally, LAB can reduce the bitterness and undesirable flavors in plant-based materials, making them more palatable. The review emphasizes the importance of LAB in improving the nutritional value and health benefits of plant-based products, while also addressing the challenges in their application. The study also discusses the potential of LAB in promoting health and disease prevention through the production of functional compounds. Overall, LAB fermentation offers a promising approach for developing high-nutrient, functional plant-based products with enhanced sensory and health benefits.