The purpose of this study is to develop the air-conditioning unit combined with the lighting unit for workspace and to supply its performance data at architectural design stage. The air-conditioning unit is one of the components of a workspace integrated unit, which can be defined as the planning unit satisfying the environmental comfort criteria of workspace. Air-conditioning diffusers are classified according to throws and features by literature review and case study. Then diffusers are combined with the lighting unit. Through the CFD simulation, the thermal performance of each unit was evaluated and finally various air-conditioning units combined with the lighting units were developed.