The aim of this study was to assess the effect of different types of catheters on the jugular vein in horses, based on frequency and type of catheter-associated complications. The study was a prospective study design. The settings for the study were at University veterinary teaching hospital. A total of 45 horses which needed a venous catheter for therapeutical use for 5 days were used for the study. Three venous catheter systems differing in diameter, length, and material (polytetrafluorethylene = PTFE 14 G × 16 cm, polyurethane1 = PU1 14 G × 13 cm, polyurethane2 = PU2 12 G × 13 cm) were applied to three groups of horses (15 horses per group) in random manner. The compatibility of the individual systems was determined by a clinical and sonographic follow-up examination of the vein and a blood follow-up examination (hematology, coagulation test). Furthermore, microbiological examinations of the skin before catheter placement and of the injection site before and the catheter tip after its removal were performed. Five of the 45 horses examined developed an aseptic thrombophlebitis, which could be diagnosed, on average, on the fifth day of examination. There was a significant difference in the development of the venous disease between the two materials (PTFE, PU) used (P = .023; 95% confidence interval, 1.19–5.55). Veins with PTFE catheters have a 2.6 times higher risk of suffering from venous disease than those with PU catheters. There was no significant difference in the development of venous disease between the diameter (12G and 14G) of the two catheter systems PU1 and PU2. Venous catheters made of PU are more convenient for use as long-term catheter systems than those made of PTFE.