Objective To investigate the prevalence of urine abnormalities for school children in Chengdu city and to evaluate the significance of urinary screening.Methods During January to December 2013,morning urine of 6 615 students were collected and screened by urine reagent paper.Two weeks later,the repeated screening was conducted in the children whose urine samples were positive for the first screening.Urine samples with positive testing results for twice were submitted to urine routine tests at local hospital,and the children with the urine positive results were defined as urine abnormalities.The children with urine abnormalities were transferred to a tertiary hospital and given treatment and follow-up.Results There were 6 615 cases receiving urine screening,including 2 624 cases (39.67 ％) of the grade I,and 3 991 cases(60.33％) at junior middle school.During the first screening,323 cases (4.83％) children had urinary occult blood positive,43 cases (0.65％) had urinary protein,20 cases (0.30％) had occult blood positive and proteinuria,and 103 cases (1.56％) had white cells in urine.During the second urine screening,62 cases (0.94％) had occult blood positive,6 cases (0.09％) had urinary protein,2 cases (0.03％) had proteinuria and occult blood positive,46 cases (0.70％) had white cells in urine.The incidence of urine abnormalities with occult blood positive,proteinuria,occult blood positive and proteinuria,and white cells in urine of children at junior middle school [1.38％ (55/3 991 cases),0.13％ (5/3 991 cases),0.05％ (2/3 991 cases),0.70％ (28/3 991 cases)] were significantly higher than those of children at primary school [0.27％ (7/2 624 cases),0.04％ (1/2 624 cases),0 (0/ 2 624 cases),0.69％ (18/2 624 cases)],and all the differences were statisticallysignificant (x2 =64.16,168.53,178.09,98.16,all P ＜ 0.05).In children transferred to a tertiary hospital for treatment,there were 4 cases with IgA nephropathy,1 case with minor glomerular abnormalities,and 12 cases with urinary tract infection.Conclusion Urinary screening is an effective way to find out kidney disease and urinary tract infection in children.Follow-ups should be strengthened.