Vesicoureteral reflux (VUR) is the commonest urinary tract diseases in children. It predisposes subjects to acute pyelonephritis, and is the most important risk factor for renal scars formation after urinary tract infections in children. Up to now, controversies still exist on the diagnosis and treatment of VUR, mainly focusing on which children should be assessed for existence of VUR, and which children should receive what kind of treatment once VUR is recognized. In research on its pathogenic mechanisms, VUR has been found to be a genetic disorder with features of racial differences, and genetic heterogeneity, etc. So far, there have not been internationally-recognized consistent major disease-causing genes. Studies to clarify the different gene mutations for causing VUR, will help to judge whether the renal scars are congenital or acquired ones, so as to make precise diagnosis and precise treatment.