Urine protein 3+ indicates kidney damage. 3+ urine protein often represents a large amount of proteinuria, and the most common diseases are glomerulonephritis, nephrotic syndrome, IgA nephropathy, diabetic nephropathy, lupus nephritis, etc. The higher the amount of protein, the more serious the damage to the kidney, which may cause the risk of hypoproteinemia, infection, blood clots, renal insufficiency, etc., and requires active treatment. Firstly, 24-hour urine protein quantification needs to be checked to assess the protein leakage, check tumor markers, autoimmune antibodies and other related indicators to indirectly determine the cause of proteinuria. Finally, kidney puncture needs to be checked to clarify the specific kidney pathology type, and according to the pathology type, choose targeted treatment options, such as microscopic lesion type, which can be treated with hormone; membrane nephropathy needs hormone combined with direct immunotherapy. In case of anti-GBM nephropathy, plasma replacement therapy is required. After clear diagnosis, a targeted treatment plan is needed.