There is not a lacking in the popular literature that advocates various beneficial effects of humor and laughter. The saying "Laughter is the best medicine" and "A laugh a day keeps the doctor away" should be familiar to everyone. Even the scientific literature has advocated the use of humor to improve doctor-patient relationship and to enable patients to better cope with their diseases. However, humor therapy can only be considered as in its early stage from the perspective of evidence-based medicine. There is still a need for evidence to support the connection between humor therapy and physical health. This article aimed to describe humor and humor therapy and to review research on humor therapy. It is hope that readers will gain an understanding of the current state of humor therapy research and to motivate research in the area of humor therapy and health.