Background: Early childhood is a key developmental period to assess social competence (SC) as experiences of peer interactions begin to accumulate. Past work suggests that temperament and forms of peer victimization (physical and relational) are independently associated with changes in SC, but less work has examined the differential effects of these factors. Objective: This school-based study examined how peer victimization and temperament influence changes in SC. Temperament was operationalized using Lahey and colleagues' (J Clin Child Adolesc Psychol, 37(4):794-807, 2008) developmental propensity model and was characterized as negative emotionality, prosociality, and daring. It was hypothesized that forms of peer victimization and negative emotionality would be inversely related, whereas prosociality would be positively related with SC. Prospective links with daring were exploratory. Hypotheses examined prospective relations with an overall SC latent variable and with its individual components (cooperation, social dominance, and positive peer interactions). Given its links with social development, executive functioning was thought to moderate these relations. Methods: The sample consisted of 300 preschoolers (M = 44.72 months old, 44% female, 62.1% White). Data was collected from multiple informants (i.e., behavioral observations, teacher-report, research assistant-report) across a 12-15-month span. Results: Negative emotionality was negatively associated with cooperation, and both negative emotionality and daring were positively associated with social dominance. Executive functioning did not moderate these associations. Conclusions: This study provides a nuanced approach to the study of SC by accounting for both dispositional and interpersonal effects on SC. Moreover, these findings highlight that development of SC may be better understood by examining its individual components.