Based on the evidence that emotion regulation difficulties underpin many mental health struggles during adolescence, including substance use disorders (SUDs), we focused on distress tolerance as a particularly salient mechanism of action for bolstering emotion regulation outcomes for adolescents in early SUD recovery. Mindfulness-based interventions are effective in improving distress tolerance through teaching skills to reduce individuals’ perceived stress or feelings of crisis and increasing a sense of agency and self-regulatory efficacy. The aim of the present study was to improve emotion regulation outcomes in the student body of a recovery high school (N = 27) through six weeks of mindfulness intervention content delivered in a small-group format. Thus, we tested feasibility through recruitment and retention rates and examined preliminary efficacy outcomes from two, randomized mindfulness intervention conditions, and used a comparison group of students without an SUD diagnosis (N = 29) sampled from the community. Results indicate significant post-intervention impacts on recovery students’ depression symptomology and on two separate measures of impulsivity (t(22) = 2.358, p < .05; t(20) = 2.358, p < .05; t(17) = 3.979, p < .01, respectively), although no significant differences between intervention condition were noted. Findings from the current study echo similar studies with comparable samples. Implications for the dosage and approach of group-format mindfulness interventions for adolescent samples are discussed.