Abstract: High entropy alloys are widely used in aerospace, nuclear reactors, and chemical processing due to their superior mechanical properties, such as high-temperature strength, oxidation, and corrosion resistance. Currently, the preparation of high-entropy alloys mainly relies on pure metal elements, which leads to high manufacturing costs and limits their industrialization. Through a large number of literature research, it is found that most of the research focuses on the basic research on the preparation of high-purity nickel-based alloys by vacuum induction melting, while there is a lack of research related to the preparation of high entropy alloys. Nickel-based alloys and CoCrFeMnNi high-entropy alloys are very different in composition, and the thermodynamic and kinetic laws of impurity removal of the two alloys are not the same, so it is necessary to carry out the basic research on the preparation of high purity high-entropy alloys by vacuum induction melting. The high-purity metal raw materials for the preparation of high-entropy alloys still contain a small number of impurity elements, such as oxygen, sulfur, nitrogen, and aluminum, etc., and the presence of these impurity elements will lead to the generation of non-metallic inclusions in high-entropy alloys. The impurity elements in the high-purity metal raw materials, refining slag, refractory materials, and preparation methods have an important influence on the generation and transformation of non-metallic inclusions in high-entropy alloys. However, due to the lack of thermodynamic parameters of the above impurity elements in the high-entropy alloy melt, it is difficult to study the removal of impurity elements and the generation and transformation mechanism of inclusions in high-entropy alloys. At the same time, this paper summarizes the relationship between the purity of high entropy alloys and mechanical properties and corrosion resistance, which provides theoretical guidance for the preparation of high purity high entropy alloys.