Magnesium (Mg) deficiency is known to promote vascular and cardiac dysfunctions such as atherosclerosis. This study investigated the effect of oral MgSO4 therapy to improve lipid profile and serum oxidized LDL level and its receptor (LOX1) in moderate coronary atherosclerotic patients. In this randomized double-blind placebo-controlled clinical trial study, 64 patients with moderate coronary artery disease were selected according to angiography findings. Participants were divided into 2 groups including Mg-treated (n = 32) and placebo (n = 32) The patients received either placebo or MgSO4 supplement capsule, containing 300 mg MgSO4 for 6 months on a daily basis. Lipid profile, HbA1c, 2h postprandial (2hpp) blood glucose, fasting blood sugar, serum glutamate oxaloacetate transaminase (SGOT), serum glutamate pyruvate transaminase (SGPT), oxidized low-density lipoprotein, and lectin-like ox-LDL receptor 1 (LOX1) concentrations were measured at baseline and every 3 months. HbA1c, serum LOX1, and oxidized low-density lipoprotein concentrations were significantly lower in the Mg-treated group than the placebo group 3 months after MgSO4 administration. 2hpp, serum low-density lipoprotein cholesterol, SGPT, SGOT levels, and HbA1c levels significantly improved in the Mg-treated group compared with the placebo-received group. Overall, the results of this study showed that magnesium treatment improved some of the major risk factors of atherosclerosis. According to the results of liver function tests (SGOT and SGPT), magnesium therapy seems to be safe in patients with moderate atherosclerotic plaque. Therefore, it is suggested that magnesium to be used along with other atherosclerosis control drugs.