Brassica rapa L., a biennial herb belonging to the genus Brassica of the family Cruciferae, is a unique edible plant resource with medicinal, food, and feed uses. It is rich in various functional components with high content, which vary due to different growth environments. This paper reviewed the recent research progress on the functional components of Brassica rapa L. and the development and utilization of functional foods. It introduced the research status of functional components such as vitamins, amino acids, mineral elements, polysaccharides, flavonoids, and saponins in Brassica rapa L., including their types, content, and physiological functions. It pointed out the deficiencies in the analysis and research of functional components and the development of functional foods. Simultaneously, it provided an outlook on the future development of the Brassica rapa L. industry, aiming to provide valuable references for further research on the functional components of Brassica rapa L. and promote the development and utilization of functional foods.