Humor is an important tool for expressing many emotions such as happiness, sadness, anger and surprise. In recent years, the use of humor has started to gain the quality of a therapy approach. The use of humor in therapy helps clients to express meaningless situations or inconsistencies in their lives in a humorous way by making them entertaining. At this point, it is very important for the counselor to be able to understand the purpose of the clients' arrival and their sense of humor depending on this purpose and to make interventions accordingly. Since the concepts of humor therapy and Laughter Therapy / Laughter Yoga are often used interchangeably in the literature, this study synthesizes both therapy approaches and tries to reveal their elements and importance. In this review, it is aimed to examine all aspects of the emergence of the use of humor in therapy, basic concepts, sub-dimensions of humor, counselor-client relationship using humor in therapy, humor therapy process, laughter therapy / laughter yoga process, laughter therapy / laughter yoga techniques, studies on the use of humor in therapy, why humor should or should not be used in therapy. In these respects, this study is expected to contribute to the literature and help fill the existing gaps. In addition, it is predicted that the widespread use of humor therapy and the use of humor therapy in different studies will benefit many clients and experts working in this field.