With improvements in infrared camera technology and the promise of reduced costs and noninvasive character, infrared thermal imaging resurges in medicine. The skin temperature distribution of a healthy human body exhibits a contralateral symmetry. Any disease inside body is associated with an alteration of the thermal distribution of human body. So human thermography is of unique value in studying the physiology of thermoregulation, diagnosing some diseases or evaluating the situation of human health. The physical principle of human thermography and its clinical applications are dicsussed. The latest progress of thermography, thermal texture maps (TTM) and its effectiveness are introduced.