Recently, attention and interest in mindfulness meditation has been increasing not only to the general public, but also in the application of meditation to various fields as well as psychological counseling, as it is known to improve mental health and mental and physical well-being, as well as change of brain function. In Korea, psychological counseling researchers have applied mindfulness meditation to various groups and reported the beneficial effects of mindfulness meditation. Transactional analysts are also increasingly interested in counseling and structured programs(MBTA programs) that use mindfulness meditation. In this context, it is necessary to pay attention not only to the beneficial effects of mindfulness meditation, but also to the adverse effects when using mindfulness meditation in counselling fields. The purpose of this study is to examine the positive effects of mindfulness meditation on psychological and mental health, and to examine the adverse effects of mindfulness meditation reported in foreign studies and domestic psychological counseling and treatment areas. In addition, we discussed the converging points of mindfulness meditation and transactional analysis, and suggested matters to keep in consideration as a counselor when trying to utilize mindfulness meditation for transactional analysis counseling.