Inguinal hernia is a major surgical disease in pediatric surgery, occurring in 3.5% to 5% of all mature newborns and 9% to 11% of all premature babies. The objective of this study is to analyze the predisposing factors in association with recurrences of inguinal hernias in infants and children. In the period from January 1995 to September 2001, 1,575 infants and children who had primary inguinal hernias or recurrent inguinal hernias operated on at the Department of Pediatric Surgery at Seoul National University Hospital were evaluated retrospectively. We evaluated the data by medical records and by telephone interview. The sex, age, location of hernia, comorbidity, prematurity, incarceration, interval to operation after incarceration, postoperative complications were analyzed as predisposing factors in associated with hernia recurrence. Operative findings of recurrent inguinal hernia were reviewed. The data were statistically analyzed with Pearson Chi-Square test and Fisher-exact test. A total of eighteen (1.14%) out of 1,575 patients underwent an operation due to recurrent inguinal hernia. In 5 (27.8%) out of 18 recurred patients, institution of the primary herniorrhaphy was our hospital and in the other 13 (72.2%) was outside hospital. No impact on the development of recurrences was seen for sex, age, interval to operation after incarceration, and postoperative complications. The significant predisposing factors of recurrent inguinal hernias were left inguinal hernias (p=0.002), comorbidity (p=0.002), prematurity (p=0.006), incarceration (p=0.017) and technical error of first herniorrhaphy. We expect that knowledge for predisposing factors of recurrent inguinal hernias and experienced skill of pediatric surgeons will decrease recurrence rate in primary inguinal hernia.