Social robots and chatbots are becoming increasingly significant for clinical applications in mental health services. As a means of mental health enhancement, robots can be used as counselors to help users make better decisions to improve their wellbeing. In this context, ethical aspects of both robots’ and chatbots’ application as mental healthcare improvement assistants are crucially important. In this paper, we discuss some ethical challenges associated with counselor bots and chatbots by considering the most important ethical principles of counseling and psychotherapy, such as autonomy, confidentiality, intimacy, responsibility, and reciprocity. We try to explore how these ethical values are at risk when using bots in mental healthcare practices and draw attention to the need of adjusting and re-setting boundaries and ethical rules in designing human/bot interaction.