If patients develop nephritis, whether renal puncture depends on several factors: 1, whether there are secondary factors, there are secondary factors usually need renal puncture biopsy; 2, whether there is renal insufficiency, combined renal insufficiency recommended renal puncture; 3, urine protein quantitative size, usually there are no secondary factors without renal insufficiency, urine protein quantitative <1 gram, can temporarily do not need renal puncture. If, after appropriate treatment, urine protein persists above 1 gram, then renal puncture is needed.4, renal ultrasound with renal atrophy and other contraindications can not be performed renal puncture biopsy. The purpose of performing renal puncture is as follows: I. Define the nature and pathological type of nephritis, and distinguish whether nephritis is caused by primary glomerulonephritis or secondary diseases such as diabetes mellitus and connective tissue disease through renal puncture. Primary nephritis is a kind of disease involved by body immunity, and the specific pathological types can be clarified by renal puncture, such as capillary proliferation type, membrane proliferation type, membrane type, and microscopic lesion type. Secondly, different nephritis pathology type treatment program is different, the prognosis is also different, can be through the renal puncture pathology results to formulate the treatment program, determine the prognosis.