This research evaluated the energy -saving rate of a solar air conditioning system with an absorption chiller for commercial use by annual energy simulation including absorption cycle calculation and collecting solar heat calculation. The energy-saving rate of cooling is improved by higher temperature heat collection, but the rate changes sensitively against the radiation. The energy-saving rate of heating is saturated to area of solar panel when the heating load is small. The energy-saving rates of cooling and heating are improved by heat collection on wall, but the effect is not so high.