Sub-picosecond laser pulse-initiated excitation energy transfer in a supramolecular complex (SC) placed in the proximity of a spherical metal nanoparticle (MNP) is studied theoretically. Spatio-temporal localization of electronic excitation energy in a chain-like SC is demonstrated. Related simulations are carried out in the framework of a density matrix theory which is based on a microscopic model for the SC–MNP system. The respective SC–MNP Coulomb interaction is dominated by an energy exchange coupling between the excitations of the SC and the multipolar excitations of the MNP. The nonperturbative consideration of this coupling results in a shift and a broadening of all SC exciton levels as well as in an oscillator strength change. Laser pulse-induced excitation energy localization is then explained as a combined effect of the oscillator strength change and the formation of an excitonic wave packet.