Background: The people with Down syndrome who are now adolescents can face a self-report questionnaire with guarantees of being answered with validity to evaluate areas of development that traditionally have not been able to be evaluated. This is the case of emotional intelligence, measured in this research with the Emotional Quotient Inventory: Youth Version-EQ-i:YV. Aims: To validate and analyse the scale's psychometric properties in adolescents with Down syndrome. Methods: A two-stage cross-sectional investigation was conducted. The inventory consists of 60 items that measure 5 dimensions. The test was administered to 644 adolescents with Down syndrome. We carried out exploratory and confirmatory factor analyses. Outcomes: The 5-factor structure of the test was confirmed. The internal consistency of four dimensions and the EQ-i:YV's total calculated score yielded high values. Conclusions: This new version of the EQ-i:YV represents a valid and reliable tool to assess emotional intelligence in Spanish adolescents with Down syndrome.