As subway transportation is in the limelight for the ecological and economical reasons, it is considered as a major public transportation in many cities for the future. Therefore, subway lines, stations and users are increasing every year, but there are more possibilities for users having trouble with finding present locations or destinations because of the confusing environment of subway stations, caused by similar space structure or crowdedness of advertisement. Positive color application in interior environment of subway station is considered as an effective place indicating method for its function of communication and identity. The purpose of this study is to understand the characteristics of color applications in subway transfer stations of 3 cities in east Asia which are Seoul, Hong Kong and Fukuoka by field investigation. The investigation has been proceed on 31 transfer stations of Seoul, Hong Kong and Fukuoka from February to August, 2009 by taking photographs and measuring wall colors with ‘Spectrophotometer’(Minolta CM- 2600d). Colors applied in subway stations are measured from 5 consisting zones (platform A, waiting room A, linking passage, waiting room B, and platform B). Main colors of interior walls were extracted based on the proportion of color application. The data were obtained by Munsell color system, and analyzed in terms of the using states of ‘hue’, ‘value’, and ‘saturation’. And the areas of investigation were limited to the interior walls which affect most to the perception of users among interior surfaces. The results are as follows: 1) In terms of ‘hue’, the dominant colors for Seoul are Y(43%), GY(26%) and YR(22%), for Hong Kong are Y(29%), PB(20%) and R(19%) and Y(60%), G(20%) and YR(13%) for Fukuoka. These results indicate that higher variation of colors are shown in Hong Kong where different groups of ‘hue’ are introduced, compared with Seoul and Fukuoka mainly applying colors close to group ‘Y’. And, it can be explained by Chinese cultural heritage which consider yellow as noble and divine power and red as auspicious occasion. 2) In terms of value, Seoul(7.73) and Fukuoka(7.42) shows similar average of value which appears to be higher than Hong Kong(5.72). 3) In terms of saturation, the average saturation of Fukuoka(1.67) appears lowest among the 3 cities, followed by Seoul(2.26) and Hong Kong(5.91). Hong Kong shows highest saturation which indicates that vivid colors are applied in large proportion of the wall for main color while soft and pale colors are applied in Seoul and Fukuoka, and it can be explained by Chinese traits of preferring vivid colors. 4) Regional differentiation in color application appeared generally high in Fukuoka and low in Seoul and Hong Kong. In some stations in Hong Kong, minimum as 1 or 2 colors are applied to whole 5 regions of stations and cause low regional differentiation. For Seoul, multiple colors are used in various areas but the application method are similar between 5 regions and cause low regional differentiation. For Fukuoka, different colors are used in each regions which cause high regional differentiation.