Body movements provide a rich source of emotional information during social interactions. Although the ability to perceive biological-motion cues related to those movements begins to develop in infancy, processing those cues to identify emotions likely continues to develop into childhood. Previous studies use posed or exaggerated body movements, which may not reflect the kind of body expressions children experience. The present study used an event-related potential (ERP) priming paradigm to investigate the development of emotion recognition from more naturalistic body movements. Point-light displays of human adult bodies spontaneously expressing happy or angry emotional movements were used as prime stimuli, while audio recordings of the words “happy” and “angry” spoken with an emotionally neutral prosody were used as targets. We recorded the ERPs time-locked to the onset of the auditory target from 3- and 6-year-old children, and compared amplitude and latency of the N300 and N400 responses between the two age groups in the different prime-target conditions. Three-year-old children showed an interaction between the prime and target for the N400 amplitude, suggesting that they were sensitive to the emotional congruency between body movements and words. Six-year-old children did not show this congruency effect; however, they had earlier N300 and N400 latency than the younger children, suggesting that older children may process the stimuli more quickly. Overall, our results suggest that both age groups can use naturalistic body movements to identify emotions, with developmental changes in how quickly emotional information from such body expressions are processed.