INTRODUCTION: Teachers and student teachers in Germany are a high-risk population for stress and stress-related mental health problems. This often leads to early retirement in subsequent professional life. Various trials have demonstrated positive effects of stress prevention training on the perceived stress and stress-related symptoms of teachers. Although many studies show positive effects of mindfulness-based stress interventions, there is not yet any mindfulness-based intervention for teachers or student teachers in Germany. The aim of this trial is to evaluate a training that combines mindfulness-based and cognitive interventions into one programme, addressing to the specific burdens of student teachers.METHODS AND ANALYSIS: This study protocol presents a prospective block-randomised controlled trial. Assessment will take place at three time points (baseline, post-intervention, 3-month follow-up) for an intervention and waiting control group, and at a fourth assessment point for the waiting control group after receiving the training. The aim is to evaluate the effects of mindfulness-based stress prevention on stress, psychological morbidity, burnout and self-efficacy using validated measures. Participants are student teachers from German teacher training colleges and participation will be voluntary. The targeted total sample size is 96 at 3-month follow-up. The training will comprise three 4-hour sessions conducted every 2 weeks. The control group will participate in the training after the 3-month follow-up. The allotment will be randomised with a stratified allocation ratio by gender. After descriptive statistics have been evaluated, inferential statistical analysis will be conducted using repeated measures analysis of variance with interactions between time and group. Effect sizes will be calculated using partial η2 values. ETHICS AND DISSEMINATION: Results will be disseminated at conferences, in specialist magazines and through peer-reviewed publications. The trial has been approved by the ethics review board of the local medical association, Mainz, Germany, under the reference number 837.192.16 (10511). TRIAL REGISTRATION NUMBER: DRKS00010897.