A problem frequently encountered in the use of drainage catheters is that thrombus deposition tends to clog the drainage catheters, which destroy the efficacy of the device. In this study, a new heparin-releasing drainage catheter for inhibition of thrombus formation was proposed. The heparin-deoxycholic acid (heparin-DOCA) conjugate in the polyurethane solution was introduced to the drainage catheters using a simple casting method. From the results, the internal thickness of the coated drainage catheter was 15 μm and the coated surface of the catheter was even without defects. The pressures of the coated catheter measured at 7, 10, and 14 days were 10.8 ± 6.08, 25.0 ± 9.17, and 29.5 ± 12.02 mmHg, respectively. These values are relatively lower than the value of the bare catheter, showing that the pressure value of the bare catheter at 14 days was 198.5 ± 16.25 mmHg. This can be explained by the fact that the heparin-DOCA was released effectively from the catheter more than 2 weeks after inserting the catheter, which prevented thrombus deposition or fibrin clotting. In conclusion, the heparin release system is more effective for inhibiting thrombus formation than heparin-immobilized system.