The original connotation of deqi in Neijing (Internal Classic) was explored to provide the reference for the clinical application of moxibustion. The relevant items of the original definition of deqi in Internal Classic were traced aligning with the achievements in the clinical researches on the heat-sensitive phenomena and its rule, and thus, the characteristics of deqi in moxibustion and its inducing approaches were analyzed. A new viewpoint of the connotation of deqi in Internal Classic was put forward. It is believed that deqi is not only a somatic response to acupuncture, but also a kind of comfortable mental-physical reaction related to curative effect. On this basis, it was discussed that moxibustion on heat-sensitive acupoints could induce deqi which conforms to the original definition described in Internal Classic. Additionally, the method of moxibustion for stimulating deqi, the screening of the items on deqi in moxibustion as well as the preliminary evaluation were introduced in the paper. It is suggested that the deqi in moxibustion is the comprehensive responses of the mental-physical-curative effect.