Multicomponent mind-body interventions are increasingly studied in oncology to improve patients' quality of life (QOL). However, the respective usefulness of each of their components or their long-term use by the participants are rarely assessed. In this study, 95 women with different cancer diagnoses participated in a self-hypnosis and self-care group. Different questionnaires were administrated before (T1), right after (T2), 3 to 4 months after (T3), and 1 year after (T4) the intervention. After the intervention, 97.5% of the participants regularly practiced any kind of relaxation (vs. 50% at baseline), especially hypnosis. The different components of the intervention (i.e., being in a group, hypnosis exercises during the sessions and at home, self-care tasks, and discussions during the group sessions) were all considered to be very useful (M = 6.91-7.75/10). One year after the intervention, the 10 most used techniques were mainly concrete activities to take care of oneself. This intervention seems very relevant for women who had cancer. Our results allow a first reflection about the mechanisms of action of our intervention.Registration: ClinicalTrials.gov (NCT03144154). Registered on the 1st of May 2017.