Nowadays, the detection of sucralose sodium adduct under electrospray ionization in mass spectrometry analysis is a common analysis method, but its high chemical stability is not fully understood. In this work, we use quantum chemistry calculations and mass spectrometry data to understand why sodiated sucralose presents this behavior in mass spectrometry conditions. The potential energy and the position of sodium ions were evaluated using different basis sets in order to comprehend the importance of sodiation in sucralose properties. Quantum-chemical calculations show higher reliability to explain the behavior of sucralose sodium adduct under mass spectrometry conditions, especially when its molecular geometry and potential energies are evaluated.