What is a Protein in Urine Test? A protein in urine test measures how much protein is in your urine. Proteins are substances that are essential for your body to function properly. Protein is normally found in the blood. If there is a problem with your kidneys, protein can leak into your urine. While a small amount is normal, a large amount of protein in urine may indicate kidney disease. Other names: urine protein, 24-hour urine protein; urine total protein; ratio; reagent strip urinalysis What is it used for? A protein in urine test is often part of a urinalysis, a test that measures different cells, chemicals, and substances in your urine.