<p>How to utilize focused ultrasound to achieve rapid, efficient, and safe ablation of atherosclerotic plaques (APs) is a significant challenge in clinical medicine. On the basis of the thermal damage effect of ultrasound on biological tissues, this paper proposes a thermal ablation mode for AP therapy with a single-focus, variable-frequency scanning model using a phased array. An AP model combined with fluid‒solid‒thermal conjugation is established and solved by the finite element method. The results show that the acoustic energy excited by a phased array can be precisely localized at the preset focal points in the plaque, and auto-focused heating is achieved under temperature control at 43&#xa0;°C. Multiple autofocus scans increase the area of plaque thermal ablation while protecting the normal tissue surrounding the plaque. This model provides a potential treatment option for the thermal ablation of plaques with different depths and sizes.</p> Graphical Abstract <p></p>