The main objective of the study was to validate the Schizotypal Personality Questionnaire-Brief (SPQ-B) in a sample of non-clinical adolescents. In addition, the schizotypal personality structure and differences in the dimensions of schizotypy according to gender and age are analyzed. The sample comprises 1683 students, 818 males (48.6%), with a mean age of 15.9 years (SD=1.2). The results showed that the SPQ-B had adequate psychometric properties. Internal consistency of the subscales and total score ranged from 0.61 to 0.81. Confirmatory factor analyses indicated that the three-factor model (positive, negative, and disorganized) and the four-factor model (positive, paranoid, negative, and disorganized) fit reasonably well in comparison to the remaining models. With regard to gender and age, statistically significant differences were found due to age but not to gender. In line with previous literature, the results confirmed the multi-factor structure of the schizotypal personality in non-clinical adolescent populations. Future studies could use the SPQ-B as a screening self-report of rapid and efficient application for the detection of adolescents vulnerable to the development of schizophrenia-spectrum disorders in the general population, in genetically high-risk samples and in clinical studies.