A central challenge in research on education for sustainable consumption (ESC) is to develop new approaches to engage adolescents with sustainable consumption (SC) in a way that addresses not only the cognitive but also the socio-emotional and behavioral levels. Mindfulness-based interventions (MBIs) that foster awareness, (self-)reflection, and ethical values could potentially leverage learning processes in ESC. The present study was the first one to investigate the potential effects of a consumption-specific MBI on sustainable consumption behavior (SCB) in the areas of nutrition and clothing. The eight-week long intervention was carried out with 15-year old adolescents (N = 85) directly at school. A randomized pre-post waitlist control group design with mixed methods was applied. The study revealed the strong effects of the adapted MBI on precursors of SCB and further effects not directly related to but potentially conducive for SCB. Actual behavioral effects were minor. Substantial inter-individual differences and inconsistencies between qualitative and quantitative results imply case-related effects that do not allow generalizable conclusions to be drawn. Nevertheless, the results of this pilot study indicate that combining mindfulness training with ESC formats appears to be a feasible and fruitful approach to engage adolescents with SC. Future practice and research should consider more diverse target groups, other consumption areas, and longer periods for interventions and their evaluation.