The aim of the study was to assess distorted cognitions regarding women and violence in a sample of 2,919 Basque-speaking secondary school students (mean age = 14.72, SD = 1.51). To this end, the Inventory of Distorted Thoughts about Women and Violence (IDTWV) by Echeburúa and Fernández-Montalvo (1998) was validated. It was translated into Basque using the back translation method. The CFA data show that the model with the best fit is made up by two factors and 21 items: beliefs about women (F1) and beliefs about the use of violence and abuse against women (F2). The IDTWV correlates with the Ambivalent Sexism Scale (Glick & Fiske, 1996) and the Sexual Double Standard Scale (Caron, Davis, Halteman, & Stickle, 1993). Results indicate that, on the whole, girls are less sexist than boys. Also, adolescents tend to express increasingly less agreement with sexist beliefs the older they are, and finally, the social desirability bias was found to influence girls' responses, especially among the younger age groups. In sum, it can be concluded that the IDTWV adapted to the Basque language is a valid and reliable tool.