This study addresses the relationship between individual differences regarding self-concept, measured by Self Concept Clarity (SCC) scale and Relational-Interdependent Self-Construal and relationships (RISC) scale, and diverse affective consequences after choice behavior. We hypothesized that lower self-concept clarity and higher relational interdependence would be related to increased susceptibility to choice context–for example, how a choice set is constructed based on one’s initial preference. We examined how variations in a choice set can produce different affective consequences after making choices, and investigated the underlying neural mechanism using fMRI. In this experiment, participants first rated their preferences for art posters, and made a series of choices from a presented set. After the choice task, they completed post-choice measures including preferences for the chosen posters, as well as measures of their self-concept clarity and relational interdependence. Our behavioral results demonstrated that when participants faced more conflicting choice context, self-concept clarity was related to more positive affective consequences after choice, whereas relational interdependence was correlated with a lower second-rated attractiveness of the chosen option. The neuroimaging analysis of choice-making revealed that self-concept clarity and the degree of their relational interdependence served as modulators in shaping how one perceives and experiences the same decision-making process. These results have theoretical and practical importance in that it is one of the first studies investigating the influence of the individual differences regarding self-concept on value-based decision making process among diverse choice set contexts.