<p>The incidence of spinal cord injury is high, and current treatment methods are limited, resulting in multiple complications and poor recovery outcomes. The application prospects of nanomaterials are broad, and their unique properties make them a hot topic in fields such as drug carriers, tissue engineering scaffolds, and biosensors. Nanomaterials have the potential to provide revolutionary means for the treatment of spinal cord injury by delivering drugs. This article mainly discusses the design and optimization of nano drug carriers in the treatment of spinal cord injury. Nano drug carriers improve bioavailability and reduce side effects by precisely controlling drug release. Design and optimization strategies include material selection, targeted design, and controlled release design to achieve more effective treatment. This article also explores the application of nanomaterials in improving the local microenvironment. Nanoparticles effectively reduce inflammation by regulating immune responses, clearing reactive oxygen species, and promoting nerve regeneration, creating a more favorable microenvironment for nerve repair. In addition, this article also explores the biocompatibility and safety of nanomaterials. It is necessary to evaluate their biocompatibility through tests such as cytotoxicity, tissue irritation, and in vivo toxicity, while monitoring the physical, chemical, and biological properties of nanomaterials to ensure their safety during the treatment process. Therefore, further development and innovation of nanotechnology will focus on improving material biocompatibility and precise targeting, as well as exploring new nanocomposite materials to enhance therapeutic effects, while deepening the understanding of nanoscale biological processes and promoting revolutionary breakthroughs in the field of spinal cord injury treatment.</p>