One of the most extensively grown fruit crops in the world is citrus fruit (CF), and as consumer demand increase so crop output increase. As a result, massive volumes of waste are produced each year from CF processing, which can have negative effects on the environment and public health in addition to being expensive to dispose of. The most recent signs of an economic, environmental, and pharmaceutical nature suggest that CF processing leftovers need to be converted from a waste product that needs to be disposed of to a useful resource that can be utilized again. CF residues (seeds, exhausted peel, pressed pulp, secondary juice, and leaves) are being re-evaluated more and more in light of a circular economy model in an effort to extract valuable compounds that can be used in the food, packaging, cosmetic, and pharmaceutical industries, among other industries. Nonetheless, because of their undervalued nutritional and commercial worth, the utilization of CF by-products is still restricted; therefore, in order to overcome conventional methods for their disposal, greater awareness and knowledge are required. In order to facilitate the transition to a more ecologically sustainable civilization, this chapter presents the most recent research on the medicinal potential of CF waste. There are numerous applications for citrus essential oils in the food safety and packaging sectors. They can also be used to increase the shelf life of various food goods as an alternative preservative.