The multi-lumen catheter with complex and small cross section is widely used for interventional radiology and minimally invasive surgery. It is manufactured in the polymer extrusion process with many manufacturing parameters. The profile of the extrudate is difficult to predict because it depends on the die shape and many parameters. In this paper, the effects of the manufacturing parameters for multi-lumen catheter extrusion are studied. The commercial software ANSYS Polyflow is used to simulate the polymer flow and predict the profile of the extrudate. The optimized die shape is used to achieve the target profile of the extrudate. The extrudate profiles are investigated with respect to the puller speeds at the end of the extrudate and blowing air pressure of each lumen. Circularity and major diameter are compared for the different manufacturing parameters. The effects of the manufacturing parameters on the profile of the extrudate are examined. The target profile of the extrudate is obtained with optimized manufacturing parameters.