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Introduction: Tissue engineering is a part of biotechnology that includes the development of biological implants for tissue regeneration to improve tissue or organ function. This study aimed to investigate the effect of cerium oxide nanoparticles on the interactions between adipose tissue stem cells and decellularized sciatic nerve scaffolds in rats. Materials and Methods: Rats were anesthetized by injecting a mixture of ketamine (80 mg/kg) and xylazine (10 mg/kg). Sciatic nerve fragments (15 mm) were removed above the three-pronged site in the thigh muscle and decellularized after cleaning the surrounding tissues using the Sandal method. Then, adipose tissue mesenchymal cells were implanted on the scaffold, and the growth and viability of the cells implanted on the scaffold in the presence of cerium oxide nanoparticles were measured by MTT assay. Results: The results of histological evaluations showed that the scaffolds were completely decellularized and hematoxylin/eosin and Dapi staining confirmed these results. Specialized tissue evaluation by Masson trichrome staining as well as biomechanical analysis showed that collagen and elastin fibers were relatively preserved in the extracellular matrix. Cell viability on the scaffold increased in the presence of nanoparticles. Conclusion: Cerium oxide nanoparticles increase cell stability, proliferation, and maintenance of adipose tissue mesenchymal cells and may be beneficial in the treatment of peripheral nerve lesions.