Abstract: From the atmospheric fluid equations and two-fluid equations of ionospheric plasmas coupled with each other, the coupling dispersion relation of atmospheric gravity waves and electron density perturbations in equatorial Fregion is derived and the resonant interaction between these two modes in different mediums is analyzed theoretically. The discussion shows that the gravity wave can transfer part of its energy to charged particles by resonance coupling mechanism and then induce initial electron density disrnrbanc for equatorial spead F. In the process, the resonance condition and resonance coupling are significantly influenced by plasma instabilities.