Water is one of the most important components for our life. Preservation of fresh water is one of the most important issues in sustainable development, which is called water treatment. In water treatment there are two main separated steps, separation and degradation. Many kinds of porous materials including zeolites and porous carbons were used for pollutant separation by adsorption. TiO2 was widely used for photocatalytic degradation of pollutant. Here we report new type of inorganic-organic hybrid porous material, metal-organic framework (MOF), which can adsorb pollutant from water followed by degradation of the pollutant by light irradiation. The MOF comprising porphyrin based ligand has good stability in water unlike most of MOFs. The MOF selectively adsorb a pollutant having smaller size than its pore size, which demonstrates size selective pollutant adsorption property of the MOF. In addition, porphyrin ligands decompose the adsorbed pollutant by visible light irradiation. Therefore, the porphyrin based new MOF can serve as a new material for pollutant removal in water. Details of our recent work will be presented.