The increasing global population, urbanization, and climate change have raised concerns about sustainability and food security. There is a growing demand for alternative protein-rich sources as consumers are increasingly opting for plant-based proteins over traditional animal proteins due to animal welfare, environmental concerns, and health benefits. However, plant-based proteins often exhibit challenges in food applications due to functional limitations such as low solubility and gelling properties with poor digestibility. This has inspired significant ongoing research to explore various methods and techniques to modify and enhance the application of plant proteins in foods. Ultrasonication (US) presents a nonthermal, green technology that utilizes high-frequency sound waves to yield proteins with modified functionality. Over the decades, researchers have established that US technology alters the secondary and tertiary structures of proteins, leading to improvements in protein extraction yield, physicochemical properties (zeta potential, surface hydrophobicity), functional properties (solubility, foaming, emulsifying, and gel strength), and in vitro protein digestibility, making plant proteins more suitable for a wide range of food applications. With this background, this chapter delves into the progress of the US as a transformative tool for the modification of plant proteins and emerging areas of research, challenges, and opportunities for further innovation.