Apolipoprotein A1 is the primary protein associated with HDL Cholesterol. Increased concentrations are associated with reduced risk of cardiovascular disease. Apolipoprotein B (Apo B) is an important component of lipid profife & as per Lipid Association of India (LAI 2020), it should be a target goal. Apo B is of 2 types namely Apo B100 which comes from the liver and is the major component and Apo B48 which comes from the intestine and is a minor component. Indians have higher levels of Apo B as compared to westerners. It is recommended to be measured under the following conditions: to assess ASCVD risk in patients with Diabetes/metabolic syndrome/obesity/high triglyceride or very low LDL-C concentration; in low and moderate ASCVD risk group, Apo B is moderate non-conventional risk factor; in high ASCVD risk subjects, after LDL-C and Non-HDL-C goals have been achieved. It is essential for the diagnosis of Type III hyperlipidemias.