This research aimed to assess two components of emotion knowledge (EK): receptive EK with face emotion identification and matching tasks, and emotion situation knowledge with the emotion attribution task (EAT). Study 1 assessed the development of EK in 265 neurotypical (NT) children (4 to 11 years), divided into four age groups. Overall, results showed a significant improvement of EK with age in the NT population for the three tasks, especially between the ages of 4/5 and 6/7. Children were less successful at the EAT in comparison to the other two tasks, indicating that receptive EK develops earlier than emotion situation knowledge. The presence of visual context (EAT) does not help to improve our children's overall facial emotion recognition, especially for anger and sadness, while these emotions are well recognized in isolated facial expressions (emotion identification). Study 2 compared EK between 32 children with Down syndrome (CA: M=13 years, SD = 2.13) and 32 NT children (CA: M=5.3 years, SD = 1.36): matched on a vocabulary task. Children with DS had more difficulties in EK than NT children. They had lower performances on the identification and the EAT tasks, while exhibited similar performances to their NT controls on the emotion matching task. Moreover, good abilities to identify emotion expressions seem to be a prerequisite for successful face-context recognition in NT children, but not in children with DS. Difficulties encountered by children with DS could result from executive dysfunction when dealing with complex visual information in addition to emotion processing difficulties.