The objective of this study was to evaluate the validity and reliability of OTESSED, an online test for the self-detection and prevention of risk factors for eating disorders and related problems, such as depression, social anxiety, and self-injury, in samples of male and female adolescents. Participants formed a non-probability sample of N = 577 high school students. The mean ages of boys and girls were the same (Mage = 15.61; SD = 0.73). Among the main results, scales of depression, self-injury, social anxiety, and risky eating behavior (REB) with construct validity (CFA) were obtained. The first two showed the same structure (two factors per sex), with an appropriate reliability omega value (0.92), and a similar percentage of explained variance (≥50). The REB scale presented two factors for boys and three for girls, with an appropriate omega value (0.88) and explained variance percentage (0.56). The instrument validation process was completed, meeting the discriminant validity criterion for each scale of the OTESSED.