The potency and effectiveness of an anti-bacterial catheter coated with a mixture of silver citrate, soybean lecithin and liquid silicon at the ratio of 2:2:8 were compared with those of commercially available anti-bacterial and conventional urethral catheters. This new anti-bacterial catheter showed a strong activity and excellent durability in ordinary in vitro experimental studies. In the present series we have developed new in vitro experimental models for the evaluation of anti-bacterial catheters in inhibiting bacterial ascent via intraluminal or extraluminal route. The characteristic features of the silver citrate/lecithin catheter, namely strong activity and excellent durability, were confirmed using these new models that mimic urinary catheter-associated clinical infections.