With the world’s population expected to grow, addressing global hunger sustainably requires innovative solutions. Utilizing microorganisms in the form of single-cell protein can play a crucial role in enhancing food security by offering a sustainable, efficient, and nutritionally valuable protein source that complements traditional food and feed sources. Yeasts are commonly used for single-cell protein production, and Saccharomyces cerevisiae has a profound role in this industry, drawing from its historical significance in baking and brewing. In the feed industry, S. cerevisiae, as an effective feed supplement, enhances feed efficiency, animal health, and pathogen control. This review explores various aspects of single-cell protein production, emphasizing S. cerevisiae’s nutritional benefits for animal feed as a source of proteins, vitamins, minerals, and fatty acids. Future research should optimize industrial production processes for S. cerevisiae to maximize yield and minimize costs.