1, urine specimens are collected correctly according to the requirements of the test, the retention of urine specimens and the accurate recording of urine volume is very important to ensure the reliability of test results. The container used must be clean, dry and single-use. 2, for infants and children who can not cooperate, should first disinfect the perineum, the use of plastic collection bags adhered to the urethral orifice to collect urine samples, but should be closely observed not to make the urine spill or feces mixed in. 3, women should rinse the vulva and then leave the middle urine for examination to prevent mixing with vaginal secretions. Do not leave urine for examination during menstruation to avoid menstrual blood interfering with the test. Men should avoid the mixing of semen and prostate fluid. 4, the subsequent routine urine test is susceptible to diet, exercise, medication, etc. 5, the specimen should be sent for examination immediately after retention to avoid changes and destruction of chemical substances and organic fractions (cells, tubular) caused by light and bacterial growth.