Acute pancreatitis (AP) is a significant cause of morbidity, even in children, and is frequently associated with systemic manifestations. There are many cytokines involved in the inflammatory response characteristic of this disease. Interleukin 6 (IL-6) is one of the most important cytokines involved in AP, beginning from cellular injury and continuing to the systemic inflammatory response and distant organ involvement. IL-6 is a multifunctional cytokine that regulates acute-phase response and inflammation. It is produced by various cells and exerts its biological role on many cells through its high-affinity complex receptor. IL-6 has been investigated as a predicting maker for severe forms of AP. Many studies have validated the use of IL-6 serum levels in the first 48 h as a reliable marker for severe evolution and multisystemic involvement. Still, it has not been used in daily practice until now. This review discusses the main binding mechanisms by which IL-6 triggers cellular response and the AP pathogenetic mechanisms in which IL-6 is involved. We then emphasize the promising role of IL-6 as a prognostic marker, which could be added as a routine marker at admission in children with AP.