Fine dust has emerged as a global problem. This study is an experiment to develop functional building materials that can reduce fine dust. This experiment is a basic experiment to investigate the fine dust adsorption performance of hardened body due to the incorporation of magnesium oxide TiO2 and its usefulness as a building material. Magnesium oxide was used as the binder and TiO2 was used as the adsorbent. Magnesium chloride was used as a stimulator of magnesium oxide. Test items are fine dust concentration, compressive strength, flexural strength, thermal conductivity and flowability. Results of the experiment, As the replacement ratio of TiO2 increased, the flexural strength tended to decrease gradually as the TiO2 addition rate increased. The compressive strength tends to decrease as the addition rate of TiO2 increases. The reason for this is considered that the amount of unit cement decreased with increasing replacement ratio of TiO2. The flowability was the highest when TiO2 was not replaced when compared with before and after hitting and decreased with increasing replacement ratio of TiO2. The thermal conductivity of the thermal conductivity increases as the TiO2 conductivity tends to decrease over time. Finally, the measurement TiO2 of the fine dust concentration was measured for 24 hours at 1 hour intervals. The higher replacement ratio of TiO2, the faster the reduction of fine dust. When not added, the fine dust reduction effect is insignificant, while when TiO2 is added, it can be seen that it drops to zero. In conclusion, It can be used as a heat insulator because of its low thermal conductivity, but further research is needed because its strength is reduced.