INTRODUCTION: High-grade glioma patients and their caregivers often suffer from distress and a lower quality of life. Results from studies with patients with mixed cancer entities suggest that yoga can be an effective support. However, it is unclear whether this also applies to high-grade glioma patients and their caregivers. This study aims to investigate the effects of mindfulness-based online yoga for patients and their caregivers on emotional distress, quality of life and stress-associated physiological parameters compared with a waiting control group (WCG). METHODS & ANALYSIS: The study is designed as a multicentre randomised controlled trial. Adult glioma patients (central nervous system WHO grades 3 and 4) and their caregivers will be recruited. Examined yoga instructors deliver the intervention (1 hour per week) in a synchronous format over 8 weeks via video conferencing. The WCG will receive standard care during the 8-week waiting period. Data will be collected before and after the end of the intervention and another 3 months later using questionnaires as well as blood serum and hair samples to evaluate biochemical stress parameters. Primary outcome is self-reported generalised anxiety and secondary outcomes are self-reported fear of progression, depression and quality of life as well as brain-derived neurotrophic factor (BDNF), dehydroepiandrosterone (DHEA)/dehydroepiandrosterone sulfate (DHEAS), ferritin and hair cortisol. We hypothesise better outcomes in the intervention group compared with the WCG at all measurement points. 70 patients and 70 caregivers will be recruited consecutively. Primary endpoints are significant effect detections in the Generalised Anxiety Disorder scale-7 of patients and caregivers at the end of the intervention. Analyses of covariance will be performed to analyse the treatment effects. ETHICS AND DISSEMINATION: The Ethics Committee of the University of Würzburg approved the YINOTA-O ( TRIAL REGISTRATION NUMBER: German Clinical Trials Register No. DRKS00029554.