Two studies investigated whether young children are selectively prosocial toward others, based on the others’ moral behaviors. In Study 1 (N = 54), 3-year-olds watched 1 adult (the actor) harming or helping another adult. Children subsequently helped the harmful actor less often than a third (previously neutral) adult, but helped the helpful and neutral adults equally often. In Study 2 (N = 36), 3-year-olds helped an actor who intended but failed to harm another adult less often than a neutral adult, but helped an accidentally harmful and a neutral adult equally often. Children’s prosocial behavior was thus mediated by the intentions behind the actor’s moral behavior, irrespective of outcome. Children thus selectively avoid helping those who cause—or even intend to cause—others harm.