Electroless plating is the continious formation of metallic coatings from metal ions by che-mical reduction without the use of electrical current. This is, however, more expansive than the conventional electroplating but is often used because of certain adventage. Here, general description of past research on electroless nickel plating, especially about the merits of each research was given. Part(Ⅰ) is for the conposition of solution, pretreatment and facilities of electroless nickel plating.