The purpose of this study was to examine that observer’s assessment of an embarrassed person influences observer’s behavior. Participants read a scenario in which a friend expressed embarrassment, before responding to items assessing the friend’s personality and mental state, as well as their own behavior. Four factors were included in the personality assessment (expressivity, sociability, selfishness, and inactivity), five factors were included in the inference of mental state (puzzlement, incomprehensibility, comicality, pleasure and anger), and four factors were included in the assessment of participant’s behavior (helping, avoidance, humor, and other-monitoring). To examine the effects of personality assessment or inference of mental state on observer’s behavior, structural equation modelings were conducted. These models revealed that avoidance was predicted by selfishness; that humor was predicted by sociability, selfishness, comicality, and pleasure; and finally, that other-monitoring was predicted by sociability, selfishness, puzzlement, incomprehensibility and anger. These results showed a part of process to produce observer’s behavior to the embarrassed person.