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 $15{mu}m$ 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 $10.8{pm}6.08$, $25.0{pm}9.17$, and $29.5{pm}12.02$ 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 $198.5{pm}16.25$ 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.