 Methods Study design and participants: A cross-sectional survey is carried out among children aged 0 to 14 years in Kashgar area in China. Before designed the study, we have conducted a pre-survey in a village which had 418 children by randomness clustered selected in Kashgar area. And ten children were found with urinary stone by ultrasonography. So we estimate the prevalence of pediatric urolithiasis p in this area is about 2.4 10418, with α of 0.05, a margin of error of less than 0.5, 3599 children would needed by the formula of sample size caculation.Consider a relative sampling error of 10, a predicted 20 refusal rate, and at least 4751 target children will be needed in this study. 