We often tend to fit our subjective preference with those of others after merely being faced with what other people prefer. This is known as social conformity. However, it is still unclear how the impact of such a social influence on subjective preference is modulated by the personal characteristics of the other person (e.g., whether the person is trustworthy) and the explicit memory of those personal characteristics (e.g., remembering who evaluated the objects). To clarify explicit memory's underlying role regarding social influence, we asked participants to evaluate their preference for abstract paintings both before and after observing binary choices made by others whose behaviors could be labeled as trustworthy, neutral, or untrustworthy. The results showed the following: (a) even without explicit memory of who made a choice and which painting was chosen, the participants preferred chosen over unchosen paintings; and (b) such preference changes were modulated by the subjective trustworthiness of others only when they explicitly remembered who made a choice.