Fructooligosaccharides (FOSs) are increasingly valued as prebiotics in food and pharmaceutical industries due to their health benefits. Despite extensive research, most studies on FOSs production have been limited to small-scale experiments. This review highlights recent advancements in enzymatic reactor designs that enhance FOSs synthesis, focusing on optimizing enzyme immobilization and reactor configurations. Key reactor types, including stirred tank, packed bed reactors, fluidized bed reactors, and air-lift reactors are discussed for their scalability and efficiency. Emerging technologies, like membrane reactors and basket reactors offer promising avenues for industrial-scale FOSs production. Challenges such as enzyme stability and product yield are addressed. This review provides essential insights for advancing large-scale FOSs synthesis.