Although the influence of intent understanding on children's moral development has been long studied, little research has examined the influence of belief understanding on that development. In two studies we presented children with morally relevant belief vignettes to examine the extent to which they incorporate both intent and belief information in their moral judgments. In Study 1 (N = 64), 5-year-olds with higher false belief understanding (FBU) rated agents with false beliefs as more positively intentioned in good intent trials (even though the outcome was bad) than in bad intent trials (even though the outcome was good). In contrast, 4-year-olds with higher FBU were generally unable to integrate their belief understanding with their moral evaluations, performing no better on intention questions than children with lower FBU. Neither age group significantly differentiated reward and punishments as a function of intent when a false belief was involved. In Study 2 (N = 109 children, N = 42 adults), we found that by simplifying our study design and reducing the task demands, 4-year-olds with higher FBU were able to make appropriate intent judgments. Yet, as in Study 1, all children had difficulty assigning punishment/reward based on intent. For both moral intentions and moral consequences, 4- and 5-year-olds with higher FBU differed from those of adults in several respects, indicating that moral reasoning develops substantially beyond the preschool years.