Cellulosic enzymes, including cellulase, play an important role in biotechnological processes in the fields of food, cosmetics, detergents, pulp, paper, and related industries. Low thermal and storage stability of cellulase, presence of impurities, enzyme leakage, and reusability pose great challenges in all these processes. These challenges can be overcome via enzyme immobilization methods. In recent years, cellulase immobilization onto nanomaterials became the focus of research attention owing to the surface features of these materials. However, the application of these nanomaterials is limited due to the efficacy of their recovery process. The application of magnetic nanoparticles (MNPs) was suggested as a solution to this problem since they can be easily removed from the reaction mixture by applying an external magnet. Recently, MNPs were extensively employed for enzyme immobilization owing to their low toxicity and various practical advantages. In the present review, recent advances in cellulase immobilization onto functionalized MNPs is summarized. Finally, we discuss enhanced enzyme reusability, activity, and stability, as well as improved enzyme recovery. Enzyme immobilization techniques offer promising potential for industrial applications.