Immune dysregulation is a pivotal factor in the onset and progression of various diseases. In cancer, the immune system's inability to discern and eliminate abnormal cells leads to uncontrolled tumor growth. When faced with resilient pathogens or harmful toxins, the immune system encounters challenges in clearance and neutralization. Achieving a delicate balance of pro‐inflammatory and anti‐inflammatory signals is essential in managing a range of disorders and diseases. Like in other biomedical research domains, nanotechnology has provided innovative approaches for rebalancing host immunity. Among the plethora of nanotechnology‐based interventions, the concept of cell membrane‐coated nanoparticles holds significant potential for immunomodulatory applications owing to their biomimetic properties that allow for precise interaction with the compromised immune system. This review thoroughly examines the potential of novel nanosystems for immune modulation. The exploration covers crucial elements, including the origins and characteristics of cell membranes, the methods employed for their procurement and coating, physicochemical/biological characterization techniques, and enhancement of their therapeutic efficacy via functionalization. Subsequently, case studies‐based analysis of utilizing these bioinspired nanosystems in tackling different conditions caused by immune disturbance has been comprehensively discussed.