The social functioning of adults with Down Syndrome (DS) specially influences their quality of life. Emotional intelligence (EI) plays a key role in social outcomes because it is defined as a variety of social and emotional skills that enable people to be more effective in their personal and social lives. Thus, validated EI tests for use among adults with DS must be reliable. This study aimed to evaluate psychometric properties of the Bar-On Emotional Quotient Inventory: Youth Version (EQ-i:YV) in adults with DS. A two-stage cross-sectional investigation was conducted. First, a pilot study (n = 10) was performed to test internal consistency and item analysis of the subscales; second, exploratory (n = 90) and confirmatory (n = 96) factor analyses were carried out. The 5-factor structure of the EQ-i:YV was confirmed: general mood, stress management, adaptability, interpersonal and intrapersonal. The internal consistency (alpha and split halves) of all five dimensions and the total calculated score of the EQ-i:YV yielded high values. This new version of the EQ-i:YV represents a valid and reliable tool to assess EI in Spanish adults with DS.