(1) Background: The dark triad refers to a personality configuration mainly characterized by the presence of Machiavellianism, narcissism, and psychopathy. Even though adolescence is a critical stage in the development of dark triad traits, to date, this construct has not been studied among adolescents, mainly due to the lack of a measurement instrument adapted to this population. (2) Methods: Using a sample of 1642 adolescents, an adaptation of the Short Dark Triad (SD3) is proposed for this population. To this end, we performed a confirmatory factor analysis of the scale and examined its reliability and the intensity of the dark triad components by sex and sexual orientation. (3) Results: The adapted version of the scale (The Short Dark Triad—Adolescent Version; SD3-A) yielded good psychometric results. Confirmatory factor analysis corroborated the theoretical model of the three factors of dark personality. The results confirmed the greater presence of dark traits in male adolescents, and differences were observed based on sexual orientation. (4) Conclusions: The Short Dark Triad—Adolescent Version (SD3-A) is an effective and comprehensive instrument for the estimation of dark traits in adolescents and can be used as a screening test for this population.