Redox-dependent hydrogen bonding has been a subject of extensive attraction since it provides a basis for external control for synthetic supramolecular system such as sensors, molecular electronics, and molecular machines. We performed density functional theoretical calculations on the nitrobenzene/arylurea interactions in order to understand the bonding and its dependence on the reduction/oxidation. We calculated the binding energy in the reduced and oxidized states and correlated the energy differences with the shift in half-wave potential, Delta E-1/2, for different p-substituted nitrobenzene/diphenylurea pairs.