We have developed an automated surveillance system to detect bloodstream infection (BSI) occurring after endoscopic retrograde cholangiopancreatography (ERCP). We retrospectively applied this automated surveillance tool to all patients who underwent ERCP at out institution between July 2004 and April 2006 to determine the baseline rates of BSI after ERCP and identify the epidemiology of the pathogens. A total of 2052 ERCPs were performed during the study period; 46 BSIs occurred within 30 days after ERCP (overall rate of post-ERCP BSI, 2.24/100 procedures). The most commonly isolated organisms were Enterobacteriaceae (n = 18; 29%) and enterococci (n = 14; 22%). Because invasive procedures are performed in various outpatient and inpatient settings, novel methods are needed to conduct effective surveillance for infection.