Abstract Background While adverse impacts of climate change on physical health are well-known, research on its effects on mental health is still scarce. Thus, it is unclear whether potential impacts have already reached treatment practice. Our study aimed to quantify psychotherapists’ experiences with patients reporting climate change-related concerns and their views on dealing with this topic in psychotherapy. Methods In a nationwide online survey, responses were collected from 573 psychotherapists from Germany. Therapists reported on the presence of such patients, their socio-demographic characteristics, and climate change-related reactions. Psychotherapists’ views on dealing with this topic in psychotherapy were also assessed. Descriptive statistics were used to analyse the responses. Results About 72% (410/573) of psychotherapists indicated having had patients expressing concerns about climate change during treatment. Out of these therapists, 41% (166/410) stated that at least one patient sought treatment deliberately because of such concerns. Patients were mainly young adults with higher education. Most frequent primary diagnoses were depression, adjustment disorder, and generalized anxiety disorder. Psychotherapists having encountered such patients differed from those without such encounters in their views on potential functional impairment and the necessity to target the concerns in treatment. Although 79% (326/415) of all respondents felt adequately prepared by their current therapeutic skills, 50% (209/414) reported a lack of information on how to deal with such concerns in therapy. Conclusions Results indicate that psychotherapists are frequently confronted with climate change-related concerns and regard the mental health impact of climate change on their patients as meaningful to psychotherapeutic care. Regular care could be improved by a continuous refinement of the conceptualization and knowledge of the mental health influences of climate change. This would allow providing tailored methods of assessing and addressing climate change-related concerns in practice.