Cupping therapy (CT) is one of the oldest medical techniques available, and is still used in several cultures instead of or as an adjunct or complement to ‘western academic' medicine. Moreover, CT (wet or dry) is claimed to have therapeutic effects in many types of disorders which do not fully respond to conventional medicine or for which no effective treatment is available. However, no recent reviews of the clinical practice of cupping are available to the best of our knowledge. We describe the applications of CT as used in Traditional Iranian Medicine (TIM). Several databases were searched for relevant literature. In addition, we studied the main traditional treatises on TIM regarding the history and practice of CT. Information about current practices was obtained from a systematic survey among practitioners. Our results suggest that CT is currently prescribed for up to 120 diseases and disorders that are difficult to treat, including cutaneous (21.7%), musculoskeletal (15%), and central nervous system (13.3%) disorders. Moreover, TIM treatises note 25 specific sites on the body surface which correspond to certain diseases, and on which wet-cupping therapy has therapeutic effects. Additional clinical studies of CT may lead to findings on new therapeutic methods and may shed light on mechanisms of disease and illness that are not fully understood in conventional medicine.