The investigation focuses on basic and non-basic color terms, perceptions of color and altitudes toward colors of representatives of the four ethnic groups in the study areas. It is found that the Tai Lue, Lua Thin, Green Hmong and Skaw Karen have 12, 5, 6 and 5 basic color terms respectively and their basic color term developments are at the 7, 5, 5 and 4 levels respectively. There are three methods regarding the formation of new terms for non-basis colors. They include compounding color terms, compounding color terms with modifiers, and using other specific words as non-basic color terms. Tai Lue, Lua Thin and Green Hmong use the second method the most, while Skaw Karen use the first method the most. All ethnic speakers use the last method the least. In regard to perceptions of color and attitudes to color, it is found that all ethnic informants have a similar perception on the foci points of all colors. As for color boundaries, all informants have the green color boundary the most compared with other color boundaries. Regarding their attitudes toward colors, they have a positive attitude toward bright colors and a negative attitude toward gray and light colors (p. iv).