Recently, functional building materials have been developed and introduced to the market. Many building materials emit volatile organic compounds(VOCs) which have the potential to affect health and comfort, and moisture problem has a major role also being established in indoor air quality (1AQ) problems. The purpose of this study is to evaluate the performance of reduction of HCHO using the gupsum board and water vapour adsorption/desorption property for ceiling board for mock-up test room and test house. The mock-up test is conducted according environmental standard method for indoor air quality of the ministry of environment. The results of this study are as follows, the reduction of HCHO gypsum boards are showed an effect to reduce the formaldehyde(HCHO) concentration of mock-up test room and test house. The indoor humidity is also showed to be lower than the general ceiling materials, since there is increased in the absorbed indoor humidity by using a humidifier with moisture adsorption/desorption ceiling materials. In natural conditions, moisture adsorption/desorption ceiling materials is showed a higher humidity than general ceiling materials constructed in the mock-up test room. However It changes of moisture adsorption/desorption is not appeared in test house. Therefore, in case of decreasing and increasing in humidity, these materials can be offset by reduction of HCHO using the gypsum board.