Chylothorax can be classified into traumatic and nontraumatic based on the etiology. Nephrotic syndrome is a very rare cause of nontraumatic chylothorax in adults. A 66-year-old woman with membranous nephropathy who was non-compliant with her management, presented with dyspnea, and was found to have a large right sided chylothorax. Her chylothorax was secondary to membranous nephropathy after excluding other causes, which has been rarely reported in literature. This case highlights the possibility of nephrotic syndrome causing chylothorax, especially in patients with undiagnosed nephrotic syndrome or patients non-compliant with their management. When evaluating a patient with chylothorax, providers should consider nephrotic syndrome in the differential diagnosis. Chylothorax can be secondary to nephrotic syndrome which has been rarely reported in literature.Providers should be aware of nephrotic syndrome as a cause of chylothorax especially in patients with undiagnosed nephrotic syndrome or non-compliance with their management.Treatment of underlying cause is usually sufficient for spontaneous resolution of chylothorax with or without pleural fluid evacuation.