<p>The paper presents a new form of multi-cubic mappings and establishes that these mappings can be unified into a single equation. Also, a system of functional equations defining multi-Jensen-cubic mappings is unified into a single equation. The generalized Hyers-Ulam stability of multi-Jensen-cubic mappings has been demonstrated by using a fixed-point approach in Banach spaces. Furthermore, several corollaries have been presented corresponding to some well-known stability results on multi-cubic and multi-Jensen-cubic functional equations. In addition, we present an illustrative example for the stability result and a counter example to show that the stability does not hold under certain conditions.</p>