Copper deficiency myelopathy is a rare and underrecognized cause of progressive myeloneuropathy that mimics vitamin B12-related subacute combined degeneration. We describe a 45-year-old woman who presented with several months of ascending lower extremity numbness, painful paresthesia, and weakness. Her history was notable for prolonged high- dose zinc supplementation initiated for immune support following the COVID-19 pandemic. MRI demonstrated dorsal column demyelination, and laboratory evaluation revealed anemia, leukopenia, and significantly low serum copper and ceruloplasmin levels with elevated zinc, confirming zinc-induced copper deficiency. The patient was treated with intravenous copper followed by oral copper supplementation, resulting in partial symptomatic improvement. Although partial improvement was achieved, persistent neurologic deficits remained at discharge. This case highlights excessive zinc intake as a preventable cause of copper deficiency myelopathy, and it emphasizes the importance of thorough supplement history and nutrient evaluation in patients presenting with unexplained myelopathy and cytopenias. Increased clinician awareness is critical, as delayed diagnosis may lead to incomplete neurologic recovery.