Epidural anesthesia is a technique of regional anesthesia in which the spinal nerves are blocked as they pass through the epidural space. The current study was conducted to determine the extent of contamination of epidural catheters and to attempt to idntify the factors contributing to contamination. The catheters removed from fifty patients were studied, two cultures were taken from each catheter and the following results were obtained. 1) Catheter tips(20%) in ten cultures and portions of the catheter located in the subcutaneous tissue in nine cultures(18%) were found to be contaminated. 2) Staphylococcus epidermidis was found in eight patients, and staphylococcus aureus and xanthomonas maltophilia were found in two patients each other. 3) In the contaminated populations, no significant difference between the growth rate of organisms and the factors in relation to the duration of catheter implantation, age of the patients and the site of catheter inserition was found.