An object of the present invention is to provide a method for suppressing surgical site infections (SSI) that have occurred at extremely high incidence rates at the time of surgical operations and particularly surgical operations on digestive system organs, and to provide a column to be used for the method. According to the present invention, a method is provided for suppressing surgical site infections, which comprises the steps of: (a) administering a chemotherapeutic drug for treating and/or preventing a surgical site infection and (b) collecting blood from a surgical subject and removing leukocytes that comprise neutrophils from the blood during or within 24 hours after surgical operation, and then returning the blood from which the leukocytes have been removed to the surgical subject. The present invention also provides a column for blood circulation which is filled with a carrier having affinity for leukocytes comprising neutrophils, which is used for suppressing a surgical site infection during or within 24 hours after surgical operation on a digestive system organ.