Transactional Analysis (TA) is not only a theory of personality and relationships but also a theory of social interaction or interpersonal communication as well as a system of group and/or individual psychotherapy. At abroad, TA plays an important role in psychological counseling and psychotherapy as well as in the other fields, such as the school education, the organizational management and the communication trainings. In 2012, with the foundation of Chinese Transactional Analysis Association (CTAA) and the beginning of the Chinese transactional analysts training, more and more experts and amateurs devote to the study, practice and communication of TA. This article demonstrates the development, main concepts, application of TA and makes a brief evaluation. The aim is to make TA to be comprehended more widely and to promote its applications and communications.