The thermal rewritable marking media are now attracting attention because they are useful for the protection of the environment and the indication of information on cards. They may be divided into two types from the principle of rewritable change that are the physical change and the chemical change types. The physical change types may be promising for practical use, because they are high durability and the control of cooling or heating rate for image formation and deletion is not necessary. The image contrast of the chemical change types is excellent due to using leuco dye. The both types are on the market in Japan for the indication of figures on the cards. The development of new application using these media is expected.