Electrophoresis is a separative technique based on migration of charged particles in electric field. This technique requires an electrophoresis unit and a power pack. Different types of support media such as paper, agarose, starch gel and cellulose acetate are used for separation of substances. Electrophoresis finds its application in separation of serum proteins, lipoproteins, isoenzymes, hemoglobin variants, etc. In this chapter, basic principles, instrumentation, and procedure for serum protein electrophoresis are elaborated.