Good mental health enables individuals to cope with the normal stresses of life. In Germany, approximately one-quarter of the adult population is affected by mental illnesses. Teletherapy and digital health applications are available to bridge gaps in care and relieve healthcare professionals. The acceptance of these tools is a strongly influencing factor for their effectiveness, which also needs to be evaluated for AI-based conversational agents (CAs) (e. g. ChatGPT, Siri) to assess the risks and potential for integration into therapeutic practice. This study investigates the perspectives of both the general population and healthcare professionals with the following questions: 1. How frequently are CAs used for mental health? 2. How high is the acceptance of CAs in the field of mental health? 3. To what extent is the use of CAs in counselling, diagnosis, and treatment acceptable? To address these questions, two quantitative online surveys were conducted with 444 participants from the general population and 351 healthcare professionals. Statistical analyses show that 27 % of the surveyed population already confide their concerns to CAs. Not only experience with this technology but also experience with telemedicine shows a higher acceptance among both groups for using CAs for mental health. Additionally, participants from the general population were more likely to support CAs as companions controlled by healthcare professionals rather than as additional experts for the professionals. CAs have the potential to support mental health, particularly in counselling. Future research should examine the influence of different communication media and further possibilities of augmented intelligence. With the right balance between technology and human care, integration into patient-professional interaction can be achieved.