Due to rapid growth of nail art industry, various materials and expression tools are have been developed. Increasing number of consumers favor diverse nail art techniques including painting and artificial tips in addition to basic care such as cuticle trimming or coloring. Accordingly, the diversity of polish colors has been settled as a concept of total fashion in addition to the clothes and accessories. As the result, nails may be damaged or discolored. A study the nail discoloration by using polish was purposed that contribute to the development of nail protective products. The tests were conducted with 20 college students for six months from March 3 to Aug. 28, 2009, using digital camera as the measurement apparatus. The students were classified into two groups which applied bright polish (white, beige, pink series) and dark polish (purple, blue, black series), and then divided into the groups applied and not applied the base coat which is known to be effective in preventing nail discoloration, and the groups applied and not applied tonic. The students applied polish for one week, and removed the polish with remover and photographed to examine the degree of nail discoloration. Dark colored polished resulted in earlier coloration and discoloration than the bright colored ones. Base coat could prevent coloration and the color changes of hyponychium and eponychium were lighter than the cases not applied with base coat. Tonic could delay coloration and reduced the color changes of hyponychium showing that tonic was effective for preventing coloration and discoloration of nail in addition to nutrition.