Dextran-methacrylate hydrogel was photo-cured onto hydrophobic PET fabrics to increase the hydrophilicity and decrease the static electricity. A novel photocrosslinking technique was applied to PET fabric treatment. Photocrosslinkable hydrogel precursor, dextran-methacrylate, was synthesized. A solution of dextran-methacrylate was sprayed onto PET fabric and photocrosslinking was conducted under a long-wave UV lamp (365 nm). The dextran-hydrogel treated PET showed a high increase in moisture content. As the hydrogel concentration increased, the moisture content of hydrogel treated PET increased gradually. Electric resistivity of dextran-hydrogel treated PET decreased with an increase in hydrogel concentration. Environmentally-friendly dextran hydrogel treated PET showed higher moisture content and a lower static electricity compared with those of untreated PET. However, other properties such as air permeability, whiteness, UV protection factor, and easy-care property were not significantly changed upon hydrogel treatment.