It is very important to understand objectively the Qi variation induced by the reinforcing-reducing manipulation method in the therapy of acupuncture. The Qi variation in the meridian treated by O-Haeng Reinforcing-Reducing Manipulation Acupuncture Method and the recovery of Five Phase deviation were measured by choosing complex acupoints. By using O-Haeng Reinforcing-Reducing Manipulation Acupuncture Method, we increased or decreased the Qi of the phase which caused the unbalance state. We observed whether the Qi of the treated meridian can be increased or not and if the state of unbaIance can be recovered. To achieve the effect of reinforcing-reducing, we need a correct choice of treating method and a selection of a proper meridian in advance. We discovered that the effects of reinforcing-reducing by each manipulation method could be superposed each other, when two counteracting O-Haeng Reinforcing-Reducing Manipulation Acupuncture Method were treated at the left and the right side of human body. We found that the Qi variation of the traeted meridian, which was induced by O-Haeng Reinforcing-Reducing Manipulation Acupuncture Method, is lineary proportioned to the reduction of Five Phase deviation.