At present, China has approved 100 kinds of foods containing proteins for special medical purposes, including nutritionally complete formulas, specific nutritionally complete formulas, protein modules, and liquid formulas. Eighty-four percent of them are produced using whey protein as the protein source. This review examines these food formulations, focusing on the application of whey protein powders in them. Based on current regulatory requirements and the characteristics of whey protein, we discuss future prospects for the application of whey protein powders in foods for special medical purposes. This review provides support for the research and development of foods for special medical purposes (FSMP).