The extraction process of the general flavonoids from Diaphragma juglandis Fructus (DJF) in Yunnan was optimized. and the ability of the general flavonoids extracts to scavenge hydrogen peroxide (H₂O₂), superoxide anion free radicals (O ·), hydroxyl free radicals (·OH) and DPPH free radicals (DPPH·) and the role of reducing fatty degeneration L02 liver intracellular total cholesterol (TC) and triglycerides (TG) were investigated. The results showed that the best extraction process for general flavonoids from Yunnan DJF was extraction with 55% ethanol at 80 ℃ for 80 min. Under the control of these conditions, the extraction yield of general flavonoids was 9.88%; 25 μg/mL general flavonoids from DJF removed 77.87% of DPPH; 89.39%, 89.56%, and 88.04% of H₂O₂, O · and ·OH were removed by 1 000 μg/mL of general flavonoids. Compared with the model group, 300 μg/mL and 400 μg/mL general flavonoids from DJF significantly reduced the content of TC and TG in steatosis L02 hepatocytes. The general flavone of DJF from Yunnan present high antioxidant activity and reduced TG and TC activities of steatosis L02 hepatocytes.