Children in foster care are a remarkably heterogeneous group regarding their adaptation, and disrupted emotion understanding is one of the processes that may lead to differential outcomes in them. Previous research has found different effects for abused and for neglected children in emotion recognition. However, very few studies have analysed more complex forms of emotion understanding in maltreated children while considering different adversity dimensions. The present study analysed associations between threat and deprivation exposure and different facets of emotion understanding in a sample of maltreated children in foster care. The sample comprised 51 children from 4 to 9 years old (M = 7.07, SD = 1.63) in nonkin foster care in Spain. We used the Test of Emotional Comprehension to measure emotion understanding and maltreatment reports to measure exposure to threat and deprivation. Threat exposure predicted enhanced external emotion understanding after controlling for age, vocabulary, and deprivation, particularly understanding emotions based on desires. Deprivation predicted worse external emotion understanding. Our findings reinforce the limits of cumulative risks models for understanding foster children's developmental outcomes and the value of assessing separately adversity dimensions when possible, given the variable relations of threat and deprivation exposure with social cognitive development.