Two plus signs of protein in urinalysis suggest the presence of proteinuria, which can be caused by a number of reasons: first, due to kidney lesions, such as glomerulonephritis, acute glomerulonephritis, nephrotic syndrome, etc., can lead to glomerular lesions and lead to the destruction of the filtration membrane, which can be accompanied by increased protein leakage, as well as decreased kidney function or edema in the limbs and facial areas, generalized hypoproteinemia, etc. Further examination of renal function and 24-hour urine protein quantification is needed to further confirm the diagnosis. Secondly, urinary tract infection can reduce the reabsorption of protein by the renal tubules, resulting in increased protein content in the urine, usually accompanied by obvious symptoms of frequent urination, urinary urgency, painful urination, not accompanied by a decrease in kidney function. Checking the kidney function is normal performance, generally after the infection control urine protein can disappear and return to normal state. Third, postural proteinuria or overflow proteinuria, such as high protein content in the diet or strenuous exercise, fever or local injury, can cause a transient increase in protein. If the relevant factors are removed, such as normalization of body temperature, rest, reduction of unnecessary and excessive physical exercise, or reduction of protein content in the diet, the protein content in the urine can be restored to a normal state.