Cardiac tamponade is a rare but life-threatening complication of umbilical venous catheterization in the newborn. Most complications from central venous catheters are related to incorrect position of the catheter and it is emphasized to confirm the position of the catheter tip after placement in order to avoid possible complications. We present an unusual complication of cardiac tamponade because of umbilical venous catheterization in a term newborn which is extremely rare with correct location of the catheter tip at the junction of inferior vena cava and right atrium. We suggest that correct position never guarantees uneventful catheterization in the newborn. In any infant with a central venous catheter in situ who deteriorates clinically, pericardial effusion/cardiac tamponade must be considered and appropriate action taken.