In the process of quantum satellite communication, the satellite link between the quantum satellite and the ground receiver is inevitably affected by the natural factors such as rain, snow, dust, haze, and ionosphere, which results in a decrease in communication quality. However, the research on the switching strategy of quantum satellite satellite-ground links is still few in the context of dust storms. In order to reduce the effect of dust storm on the switching of satellite-ground links, we propose a switching strategy of dual-satellite satellite-ground links based on optimal entanglement. By establishing the relationship between the parameters of sandstorm and the entanglement degree of satellite-ground links, the effects of dust diffusion mode index, dust particle radius, observation height, and sand disaster coefficient on the entanglement of links are analyzed. According to the entanglement of satellite-ground links in the context of sandstorm, a new switching strategy is proposed, that is, in the case that the current dual-satellite serves a ground user, one satellite with the largest entanglement degree is selected from the multiple candidate satellites as the optimal target satellite to be switched by the link. The simulation results show that the sand dust diffusion mode index, sand particle radius, observation height, and dust disaster coefficient can lead to the significant change of entanglement degree of links. The proposed optimal entanglement-based switching strategy of dual-satellite satellite-ground links can not only reduce the impact of sandstorm on the entanglement degree, but also make link interruption disappear during the switching process. Thus the switching strategy based on the optimal entanglement degree of satellite-ground link can effectively improve the communication quality of links.