This study had two purposes: first, we investigated the factor structures of personality assessments, inferences of mental states, and behaviors toward an embarrassed person by an observer. Second, we examined whether these factors differed depending on the types of facial expressions of embarrassment. Participants were presented with scenarios in which a friend felt embarrassment. After reading the scenarios, participants were asked to respond to items regarding the friend’s personality assessments, inferences of the friend’s mental states, and the observer’s behaviors. A series of factor analyses revealed that personality assessments comprised four factors (“expressivity,” “sociability,” “selfishness,” and “inactivity”), inferences of the friend’s mental states comprised five factors (“puzzled,” “incomprehensibility,” “comicality,” “pleasure,” and “anger”), and the observer’s behaviors comprised four factors (“helping,” “avoidance,” “humor,” and “other-monitoring”). To examine whether these factors differed depending on the type of facial expression, one-way ANOVAs were conducted. They revealed that for personality assessments and inferences of mental states, the “sociability” score and “pleasure” score were higher for two types of embarrassed facial expressions that contained smiles as compared to ones that did not contain smiles. Moreover, for the observer’s behaviors, “humor” score was higher for facial expression that included smile and tongue as compared to ones that did not include those features. Thus, the presence or absence of a smile in facial expression affects observer’s personality assessments, inferences of the mental states, and behaviors toward the embarrassed person.