Abstract: As a fundation of SEA for conservatively or non-conservatively coupled systems under correlative excitations, power flows between and energy distribution in two coupled oscillators under proportionally correlative excitations are studied mainly in this paper. Theoretical relationships among power flows and time averaged vibrational energy of the oscillators, as well as power balance equations and energy ratio of them, are derived. Further along, power flows, energy distribution, and power balance equations of the system in conservative or non-conservative coupling and under proportionally correlative excitations are discussed in details with comparison to characteristics of those in non-correlative excitations. Numerical results supporting the basic theory are given too. Results show that the power flows and energy distribution of the oscillators under correlative excitations, either conservative or non-conservative coupling, are much different with those in the condition of non-correlative excitations.