Abstract: The present invention provides a 1,2,4-triazine-3,5-dione compound, a preparation method therefor, and an application thereof. The 1,2,4-triazine-3,5-dione compound having a structure represented by formula (I) provided by present invention has a selective agonistic effect on THR?, and the activity, selectivity, and metabolic stability thereof have significant advantages over disclosed compounds, and can function as a therapeutic and/or preventive drug for thyroid hormone receptor related diseases, comprising, but not limited to, obesity, diabetes, hypercholesterolemia, hyperlipidemia, hypertriglyceridemia, liver steatosis, non-alcoholic fatty liver disease, nonalcoholic steatohepatitis, familial hypercholesterolemia, dyslipidemia, atherosclerosis, hypothyroidism, and thyroid cancer.