Every interventional procedure can result in infectious complication even though its incidence is very low. Increases in both indication of procedures and number of immunocompromised patients are likely to result in increase of infectious complications. However, no randomized controlled trials to evaluate the effectiveness of prophylactic antibiotics in interventional procedures have ever been performed. This study was performed to investigate the actual pattern of practice and awareness of medical providers concerning the antibiotic prophylaxis following vascular and nonvascular interventional procedures. A questionnaire regarding prophylactic antibiotic usage was sent to the interventional radiologists in 40 hospitals. A total of 12.2-30.3% responders used prophylactic antibiotics for vascular procedure. More than 80-90% of responders answered that vascular procedures except catheter insertion, are not clear indications of prophylactic antibiotics. In contrast, 31.3% and 51.5% of responders used prophylactic antibiotics for genitourinary and biliary drainage respectively. About 60-70% of responders considered both genitourinary and biliary drainage as clear indications of antibiotic prophylaxis. Further study assessing the appropriate antibiotic usage in interventional procedures is warranted.