Oxidative stress and inflammation are key pathological features of atherosclerotic plaques. Numerous nanomedicines have been developed to alleviate oxidative stress and reduce inflammation within plaques. However, nonbioactive carrier materials reduce the bioavailability of nanomedicines and may pose potential biological toxicity. In this study, we utilized the unique amphiphilic chemical structure of lipoic acid (LA) to prepare LA nanoparticles (LA NPs) via a self-assembly method. Leveraging the inherent anti-inflammatory and antioxidant properties of LA, these NPs were used for the treatment of atherosclerosis. In an inflammatory macrophage model, LA NPs exhibited superior anti-inflammatory activity compared to free LA. Through ultrasound imaging and pathological methods, we discovered that LA NPs demonstrated nice antiatherosclerotic effects in an atherosclerotic mice model. Immunofluorescence analysis further indicated that the antiatherosclerotic effects of LA were associated with the alleviation of oxidative stress within the plaques, reduced macrophage infiltration, and downregulation of inflammatory cytokine levels. Therefore, LA NPs offer a promising therapeutic strategy for the treatment of atherosclerosis.