The purpose of this study wsa to explain purchase intention of consumers for fair trade coffee as an ethical consumption product. To achieve the purpose, the theory of planned behavior was modified by including the additional factors such as ethical obligation and self-identify besides attitude, subjective norm and perceived behavioral control and tested as a structural equation model by using LISREL 8.52 package. First, consumers presented to have more positive attitude, while they would not feel higher pressure from others(the subjective norm). Also they would feel more difficulties(perceived behavioral control) if they purchased the coffee for information, price, availability etc. In addition, they would feel some ethical obligation and self-identify with the coffee and would like to purchase the coffee. Second, as the result of testing the theory of planned behavior, the purchase intention was found to be significantly influenced not by the subjective norm and perceived behavioral control but by consumer attitude. Furthermore, the additional factors(ethical obligation and self-identify) were found to significantly influence to the purchase intention. Thus, some other factors related with personal values such as ethical obligatio and self-identify shoulc be included into the model to raise the explanatory power. Third, consumer attitude was found to be significantly influenced by ethical obligation and self-identity. In other words, the purchase intention of the coffee might be influenced directly by the value of the ethical obligation and self-identity and indirectly by them via consumer attitude. Thus, the importance of ethical obligation and self-identity should be paid attention for explaining purchase intention of the ethical consumption product such as the fair trade coffee.