ObjectiveWe aimed to evaluate the causes of complications following surgery for inguinal and femoral hernia, using surgical site infection (SSI) and recurrence rate as indicators of outcomes to consider appropriate treatments. MethodsWe retrospectively assessed the medical histories of 1,098 patients with adult inguinal and femoral hernias who underwent herniorrhaphy between July 2010 and March 2019. Using SSI and recurrence rate as indicators of outcomes, we statistically assessed the influence of preoperative and operative conditions on surgical outcomes. ResultsThe occurrence of postoperative SSI was significantly more frequent in patients who experienced a long surgical duration, excessive blood loss, and incarceration; underwent emergency surgery and bowel resection; and in whom no mesh sheet insertion was performed. There was no correlation between mesh use and SSI in cases that did not require emergency incarceration repair. For cases involving hernia incarceration, the use of a mesh sheet was avoided to prevent potential infection, which could explain the high incidence of SSI in cases where mesh was not used. The hernia may have recurred due to technical issues during the procedure, as well as failure to ligate the hernia sac. ConclusionsSelecting the appropriate surgical method for hernia repair may reduce the incidence of SSI. If manual reduction of inguinal hernias is not possible, an appropriate surgical procedure should be determined based on laparoscopic findings in facilities where laparoscopic hernia surgeries are frequently performed. Moreover, in cases without infection and bowel resection, mesh use may be beneficial. Recurrence can be prevented by ligating the hernia sac during surgery and solving relevant technical problems.