The most prevalent form of heart disease and the main cause of death in both developed and developing nations is CAD. It happens when "plaque," or cholesterol or other fatty deposits that accumulate on the inner wall of the artery, narrows or blocks the arteries that deliver blood to the heart. Over time, chest pain might develop as a result of the reduction in blood flow to the heart caused by this plaque accumulation. The study was designed to find if Arginase acts as a biomarker for diagnosing Coronary Artery Disease (CAD). A total of 90 individual samples were included in the present study, the control group consist of 40 healthy individual samples, while the CAD patients were 50 individual samples. Some biochemical parameters such as fasting blood glucose (FBG), troponin I(TnI), high sensitivity C-reactive protein (hs-CRP), lipid profile, lactate dehydrogenase (LDH), and Arginase activity were analyzed. The results of the current study showed no significant differences in the average age of patients (67.00±6.78) when compared with the control group (61.10±6.46), P>0.05. A significant increase Was found in the FBI level, cholesterol, triglycerides, very low-density lipoprotein (VLDL), low-density lipoprotein (LDL), TnI, hs-CRP, LDH, and Arginase activity in the patient's group when compared with the control group. While significant decrease (P<0.05) was revealed in the high-density lipoprotein (HDL) level in CAD patients in comparison to the control group. Also, there was a positive significant correlation between Arginase activity with each age and FBG. As for the ROC operator curve for Arginase, it was found that the area under the curve (AUC) was 0.953 with a sensitivity of 90%, and specificity of 95%. The results in the present study indicate a possible use of Arginase as a diagnostic marker for CAD.