Using event-related potentials (ERPs), this study examines how trait information inferred from behaviors is associated with person names. In linguistic discourses, person names were associated with descriptions of either positive or negative behaviors. In a subsequent explicit evaluation task, the previously described person names were presented in isolation, and the participants were asked to judge the emotional valence of these names. We found that the names associated with positive descriptions elicited a larger positivity in the ERP than the names associated with negative descriptions. The results indicate that the emotional valence of person names attached to person perception can be dynamically influenced by short descriptions of the target person, probably due to trait inference based on the provided behavioral descriptions.