<p><i>Morus alba Linn.</i> (White Mulberry) is an ancient medicinal and functional food traditionally used throughout Asia and increasingly found worldwide as a sustainable crop for bioactive compounds of wide-ranging health-promoting activity. This narrative review critically examines its therapeutic, pharmacological, and functional food uses by synthesizing evidence from in vitro, in vivo, in silico, and clinical studies. The crop’s broad phytochemical profile—comprising flavonoids, alkaloids, stilbenes, polysaccharides, and anthocyanins—supports multifarious bioactivities like antioxidant, anti-inflammatory, antimicrobial, antidiabetic, cardioprotective, and neuroprotective activity. Experimental and preclinical models exhibit robust redox-modulating and metabolic regulatory activities, whereas human trials offer promising evidence for glycemic regulation, lipid equilibrium, and enhanced metabolic well-being. Nanotechnology-based formulations of Morus have improved solubility, bioavailability, and targeted delivery of the principal constituents, enhancing their therapeutic importance. Recent developments in functional foods, such as the use of mulberry-derived products (e.g., tea, yogurts, and fortified foods), further demonstrate their potential to maintain gut microbiota equilibrium, manage weight, and ensure cardiovascular health. Safety assessments reveal a wide margin of tolerance, although potential gastrointestinal effects and herb–drug interactions need additional research. On a broad basis, <i>Morus alba Linn</i>. is a novel and eco-friendly functional food component with multitargeted pharmacology and nanotechnology-based benefits. Standardized formulations, optimal doses, and optimally designed clinical trials should be highlighted in forthcoming research to facilitate their safe entry into nutraceutical and therapeutic applications.</p>