Central Venous Catheters insertion is a very common procedure performed at the operation room and the Intensive Care Unit. In the paediatric population they are frequently used to administer fluids, blood products, resuscitation drugs, parenteral nutrition and chemotherapy. One of the reported complications, though a less commonly described one, is the inappropriate position of the tip of the CVC in a vessel other than the superior vena cava. In this study, we initially present the anatomy of the superior vena cava system and that of the internal jugular vein, the optimal catheter tip position as well as the possible suboptimal catheter tip locations. Subsequently, paediatric chest X-rays of our hospital with catheter tip malpositioning are illustrated, after internal jugular vein catheterization. Following, we discuss possible mechanisms of central venous catheters malpositioning, signs and symptoms which could help us identify a wrong placement and also how to prevent as well as how to fix one. Finally, an interrelation between malpositioning, malfunction and the existence of infection or thrombosis is investigated. Our study concluded that the right internal jugular vein should be the first choice in all cases of vessel implantation, mainly based on our statistical analysis results, which suggested that this vessel was associated with the least possibility of erroneous catheter placement. Another important clue of our study is based on the fact that the inappropriate positioning of a central venous catheter over the long term could be a significant predisposing factor of malfunction, along with infection and thrombosis.