Based on a literature review and on the assessment of the author’s experience during the round table ‘The psychology of religion: an inter-disciplinary approach’ at Saint Petersburg State University, the article reflects on the current state of Russian and foreign thought regarding the psychology of religion and religious psychology. The psychology of religion is consideredas a branch of psychology, while religious psychology is consideredas a part of theological knowledge. The state of the psychology of religion is examined in various Christian confessions. The author pays particular attention to the state of Islamic psychology in Russia and abroad; the article considers the history and prospects of the discipline and its major fields of research and practical activities. The article also highlights that the development of the psychology of Islam will occur in close cooperation between the specialists in psychology and Islamic theology, while the development of Islamic theology will be a basis for understanding of Muslims’ religious beliefs.