Nursing care insurance companies in Germany have the legal mandate to develop measures to strengthen the health resources of residents of nursing homes. The present study aimed to examine a mindfulness-informed mind-body intervention (on-site and app) adapted for residents in nursing homes regarding their effect on health-related parameters.A pilot study (DRKS00030409) was carried out with three groups in twelve nursing homes (RCT). There was an on-site intervention in a group (O), an individual app application with technical support (A) and a passive control group (C). The participating residents (n=28; n=29; n=19) were cluster-randomized. Before, after, and three months after the intervention period (December 2022 - January 2023), among other things, subjective well-being (WHO-5, primary outcome) and mindfulness (KIMS-D, including four subscales) were assessed. Differences within and between study groups and participants with different participation intensity were tested. In addition, a sensitivity analysis was carried out with people who did not have severe cognitive impairments at all three survey times.Indications of differences were found in subjective well-being during the intervention period between the study groups of medium size. While a decrease was observed in the control group, there was no change in the intervention groups. When the intensity of participation was taken into account, the difference between the groups became clearer. In addition, the app group showed an increase in mindfulness (subscale ) immediately after the intervention compared to the control group.Although further studies with larger samples are needed, the results already indicate that the intervention improves the well-being and mindfulness of the target group. Individual support could explain the higher effectiveness in the app group. The influence of the Covid-19 pandemic and the season (winter) on effectiveness must also be examined.