Abstract: In this paper, a qualitative discussion and numerical calculations are made for thetopological characteristics of the nonlinear govehong equations of the excitations ofequatorial Spread-Funder existence of acoustic-gravity waves. The results show thatin detendning the pertUrbahon features of Spread-Fthe amplitudes of asoustic-gravitywaves take an important role. When the amplitude of acoustic-gravity wave is small,features of the equations' singularity are similar tOsituations without AGWs, i. e.,nonlinear resoluhons will finally stabilized to two fixed ponts, as the amplitude ofAGWs becomes larger, there will be a crihcal value. Above this value, soluhons showchaotic characterishcs, and Spread-Fwill have rich spectral components. When theamplitude of AGWs getting even larger than a second crihcal value, the soluhons ofthe system recovers from chaohc to Periodic and the features of solutions are mainlydetermined by AGWs as extemal driving souree.