In this paper, we present an investigation on thermal stability of Au-Pd eutectic nanoparticle by using molecular dynamics simulation with embedded-atom potential. The results show that the melting point of Au-Pd eutectic nanoparticle is remarkably higher than that of pure Au one but lower than that of Pd one. By the analyses of Lindemann index, it is found that Au atoms first melt, then induce the melting of Pd atoms. The temperature range of melting is broader for Au-Pd eutectic nanoparticle than that for Au and Pd nanoparticles.