In order to assess the unique contributions of non-verbal cognitive abilities and attention to young children's emotion understanding, a total of N=. 274 four-to-six-year-old children were tested individually. Hierarchical regression results suggest that the children's non-verbal reasoning abilities, their attention performance test scores, and their kindergarten teachers' attention ratings all predict their emotion understanding above and beyond their age and their receptive language skills. When the children's non-verbal cognitive ability was included as a predictor in the model, attention (in either performance or teacher rating) did not explain any additional variance in their emotion understanding. The discussion centers on relations between non-verbal cognitive abilities and emotion understanding.