The present study aimed to examine the ability to recognize basic facial emotion expressions and sensitivity to low and high intensities of sad and happy expressions. These two components of emotion processing were assessed in 47 individuals with Down syndrome (DS), divided into three age groups. Results showed that young adults (aged 18.15–30.8 years) and middle-aged adults (aged 32.2–42.15 years) had significantly higher identification scores for happiness than the children’s group (aged 10.5–16.8 years). Additionally, only the middle-aged group identified anger more accurately than the children’s group. High-intensity happiness expressions were more accurately identified than sadness across all groups, while the opposite pattern was observed for low-intensity sadness expressions. Vocabulary level was associated with the recognition of certain emotion expressions, but was not with sensitivity to emotional intensity. Contrary to findings in typical development, no association was found between the two components of emotion processing in this population. Emotion recognition in individuals with DS is influenced by age, emotion type, intensity, and task modality. Deficits may stem from inefficient perceptual strategies, such as focusing on the mouth region, and underdeveloped configural face processing. Vocabulary supports recognition of basic emotions, highlighting the role of semantic knowledge. A positivity bias favors happiness recognition, while negative emotions are often confused, potentially due to attentional and executive control difficulties. Neurological differences, including reduced gray matter and connectivity, likely contribute to persistent impairments. Understanding these complex factors is crucial to develop targeted interventions to improve emotional and social functioning in DS.