Abstract: OBJECTIVE To investigate the etiological characteristics of perioperative nosocomial infections in patients with adenoidal hypertrophy and analyze the influencing factors for the infections. METHODS A total of 182 patients with adenoidal hypertrophy who received surgical procedures in the hospital from Jun 2016 to Dec 2016 were recruited as the study objects.The incidence of nosocomial infections, distribution of isolated pathogens and influencing factors for nosocomial infections were observed. RESULTS Among the 182 patients, 41 case-times of patients had nosocomial infections during perioperative period, with the case-time infection rate 22.53%.The respiratory tract and surgical site were the major infection sites.Totally 41 strains of pathogens were isolated from submitted clinical specimens, of which 15 (36.59%) were gram-negative bacteria, 16 (39.02%) were gram-positive bacteria, and 10 (24.39%) were fungi.The result of univariate analysis showed that the incidence of the infections was associated with the disease course, operation duration, length of hospital stay, SAS score, complication with grade Ⅳ obstruction, asthma history, diabetes mellitus history and catheter indwelling (P＜0.05).The multivariate analysis indicated that the independent influencing factors for the infections included the disease course, operation duration, length of hospital stay, SAS score, complication with grade Ⅳ obstruction, asthma history, diabetes mellitus history and catheter indwelling (P＜0.05). CONCLUSION The incidence rate of perioperative nosocomial infections is high in the patients with adenoidal hypertrophy.The influencing factors for the nosocomial infections include the long disease course, operation duration, length of hospital stay, high SAS score, complication with grade Ⅳ obstruction, asthma history, diabetes mellitus history and catheter indwelling, and it is necessary to pay attention to the prevention.