This paper concerns the orbital stability for solitary waves of the long waveshort are resonance equations. By using a different method from [15], applying the abstractresults of Grillakis et al. [8][9] and detailed spectral anaiysis, we obtain the necessaxy andsufficient condition for the stability of the solitary wavs. By using a different method from [15], applying the abstract results of Grillakis et al. [8] [9] and detailed spectral anaiysis, we obtained the necessaxy andsufficient condition for the stability of the solitary wavs.