Autoimmune Diseases (ADs) encompass a multifaceted spectrum of chronic disorders characterized by an aberrant immune response against host tissues. Notwithstanding substantial progress in immunological research, current therapeutic interventions remain largely palliative, relying on broad-spectrum immunosuppressants that are frequently associated with substantial adverse effects and compromised immune defense. Currently, biomimetic nanoparticles (BMNPs) stand out as a paradigm-shifting approach in precision medicine, facilitating targeted delivery, enhanced biocompatibility, and sophisticated immune modulation. This review critically examines the therapeutic applications of BMNPs in managing autoimmune disorders, including rheumatoid arthritis, type 1 diabetes, systemic lupus erythematosus, multiple sclerosis, and celiac disease. By emulating cellular membranes, such as those of erythrocytes, platelets, and leukocytes, BMNPs acquire the ability to evade immune detection, prolong systemic circulation time, and deliver therapeutic payloads directly to inflamed or diseased tissues. The integration of BMNPs with pharmacological agents, immunomodulators, or advanced gene-editing systems like CRISPR/Cas9 has demonstrated enhanced specificity and attenuated systemic toxicity in preclinical models; notably, these platforms exhibit several- fold higher drug accumulation in inflamed tissues compared to conventional non-targeted nanoparticles. Furthermore, the utilization of BMNPs in diagnostic imaging, particularly MRI and PET, has facilitated superior disease monitoring and treatment evaluation. While challenges such as large-scale production, potential toxicity, and regulatory hurdles persist, overcoming these barriers requires establishing standardized manufacturing protocols and clear translational pathways. This article delineates the latest advancements, design strategies, and translational challenges of BMNPs, underlining their potential to reshape the landscape of aut