ObjectiveTo study the mechanism of Huanglian Jiedutang （HLJDT） in treating mice with atherosclerosis （AS） by improving ferroptosis. MethodsA total of 10 SPF C57BL/6J mice were selected as a normal group， and 50 ApoE^-/- mice were randomly divided into five groups： model group， low-dose group of HLJDT， medium-dose group of HLJDT， high-dose group of HLJDT， and atorvastatin （ATV） group. ApoE^-/- mice were fed a high-fat diet for eight weeks to establish the AS model， and at the 9th week， they were given normal saline， low， medium， and high doses of HLJDT （3.9， 7.8， 15.6 g·kg^-1·d^-1）， and atorvastatin calcium tablets （0.01 g·kg^-1·d^-1）， respectively， for a total of eight weeks. The formation of aortic plaque in mice was observed by gross oil red O staining and Masson staining. The levels of total cholesterol （TC）， low-density lipoprotein cholesterol （LDL-C）， triglyceride （TG）， and high-density lipoprotein cholesterol （HDL-C） in blood fat were measured by the automatic biochemical analyzer， and the mitochondrial structure of the aorta was observed by transmission electron microscopy. The content of serum superoxide dismutase （SOD） in serum was detected by enzyme-linked immunosorbent assay （ELISA）. The content of reduced glutathione （GSH） in serum was detected by the microplate method， and that of malondialdehyde （MDA） in serum was detected by the TBA method. The protein expression of nuclear factor E₂-associated factor 2 （Nrf2）/glutathione peroxidase 4 （GPX4） signaling pathway was detected by Western blot. ResultsCompared with those of the normal group， the contents of TC， LDL-C， TG， HDL-C， and MDA in the serum and the aortic vascular plaque deposition of the model group were significantly increased （P<0.01）， while the expression levels of SOD and GSH in serum， as well as Nrf2， solute carrier family 7 member 11 （SLC7A11）， and GPX4 in aorta were significantly decreased （P<0.01）. Mice in the model group appeared mitochondrial fragmentation and vacuolation in the aorta， volume atrophy， mitochondrial crista reduction， or a loose and disorganized form. Compared with those in the model group， the aortic vascular plaque deposition was significantly decreased in the low-dose， medium-dose， and high-dose groups of HLJDT and ATV group， and the contents of serum TC， LDL-C， TG， and MDA in serum were significantly decreased （P<0.05， P<0.01）. The contents of serum SOD and GSH and the expression levels of Nrf2， SLC7A11， and GPX4 in the aorta were increased （P<0.05， P<0.01）， and the symptoms of aortic mitochondrial vacuolation were alleviated. The number of cristae was increased， and they were ordered neatly. ConclusionHLJDT can reduce aortic vascular plaque deposition， decrease blood lipid and MDA expression， increase SOD and GSH expression， and ameliorate the pathological changes of ferroptosis， the mechanism of which is related to the Nrf2/GPX4 signaling pathway.