Polysulfone (PSF)s are amorphous polymers which possess excellent thermal stability and good optical properties. But they have drawbacks such as poor chemical resistance and high thermal expension property. In this study, we introduced crosslinkable acrylic moiety in PSF with side-chain using chloromethylation method. We prepared photosensitive PSF having methylene methacrylate side-chain from chloromethylated polysolfone (CMPSF). And we performed solvent casting films of the polysulfone methylene methacrylate (PSFMM) and produced the crosslinked PSF films via UV expose. Their properties such as the thermal, optical, gas barrier properties, and chemical resistance were measured by TGA, DSC, TMA, UV-transmittance, MOCON test, and solubility test. The crosslinked PSFMMs were insoluble in various protic and aprotic polar solvents. They have low CTE (coefficient of thermal expansion) value and gas barrier property improved according to increase of crosslinkable moiety.