According to two kinds of acupoint combination methods for Huahe and Huhe in five-door and ten-change theory proposed by the deceased Taiwanese famous acupuncturist Mr. ZHOU Zuo-yu, the origin of the change theory proposed by the deceased Taiwanese famous acupuncturist Mr. ZHOU Zuo-yu, the origin of the acupoint combination method of five-door and ten-change is introduced. This method combines traditional philosophy of Yi with medicine, which is featured with casual timing, casual pattern, capacity to be combined with TCM syndrome differentiation, specific application scope and pertinence. Some clinical cases are additionally presented to verify this method. Huhe method is mostly used for Bi-syndrome while Huahe method has better effects on internal medicine diseases. They open the new thinking methods for clinical acupoint selection.