The global consumption of tropical fruits has been increasing gradually, due to their high nutritional value and desirable sensory profile that can meet diverse consumer demands. In the fruit industry, the seeds of tropical fruits are often part of the by‐products that are commonly generated from the processing and manufacture of fresh whole fruits, ready‐to‐eat fruit salads, juices, concentrates, and dried fruit products. Currently, most of the fruit seed by‐products are subject to direct disposal or recycle in the form of the ingredients for animal feed and agricultural fertilizer. However, considering they are still rich in nutritional and bioactive components, tropical fruit seeds are hidden jewelry that can be more extensively utilized in the food industry, such as in food processing, food preservation, and the formulation of functional foods. In this review, the main components of different representative tropical fruit seeds are summarized, and the corresponding functions are elucidated. The methods on processing such fruit by‐products and the extraction of value‐adding substances from fruit seeds are compared. The potential application pathways in food industry are discussed accordingly, with further demonstration of current opportunities and main hurdles. This comprehensive review aims to capture the interests of food scientists, fruit manufacturers, and other stakeholders in the food supply chain, in order to explore the possibilities for reutilizing the functional components from tropical fruit by‐products in a broader spectrum.