: Responsible consumption is defined in environmental, cultural, economic, ethical, and social terms. The subject has been studied for at least 50 years. Currently, the description of the responsible consumer is relevant, given the climatic complications that humanity is facing. Having an instrument to identify responsible food consumption in the adolescent population will make a significant contribution to both the scientific field and group interventions. The objective of this research was to design and validate a scale to measure responsible food consumption in adolescents (Escala de Consumo Responsable de Alimentos en Adolescentes ECRAA) using a sample of 288 junior high school students. The scale has 23 items distributed in four dimensions—knowledge, attitudes, emotions, and practice—and was designed and validated with a cross-sectional study. Aiken's V coefficient was used to validate the content of the scale, a confirmatory factor analysis was used to validate the construct validity, and reliability was measured by calculating Cronbach's alpha. The ECRAA was found to have adequate properties. All 23 items received a positive evaluation from experts. The confirmatory factor analysis supported the structure with favorable goodness-of-fit indices, and the reliability of the data was found to be acceptable. Thus, the ECRAA is valid and reliable for measuring responsible food consumption in adolescents.