Considering the dramatic growth of the functional coffee market in Thailand, this study aims to investigate young adult consumer motivation and values underlying their purchases. The means-end chain (MEC) theory was applied to understand the decision making process. Thirty regular functional coffee purchasers were interviewed using the laddering interview technique. Through LadderMap program analysis, the research results showed that all young adults purchased functional coffee believing in the slimming consequence. Furthermore, this study found two different decision making patterns, those young adult working in offices considered ingredients such as white beans, no sugar, and fiber as key attributes in decision making. Whereas, those who were college students, factory workers and housewives tended to be motivated by the results of rapid dieting. Different communication strategies and channel selection for each group have been suggested as research implications.