Photocatalytic decomposition of fluroborate was studied. Unmodified, single component photocatalysts exhibited poor activities, while TiO₂ (P25) showde the best activity among them. Maximum removal ratio of fluoroborate was obtained at about pH 4. In order to enhance the activity, a variety of catalysts including metal-doped and composite semiconductors were prepared. In the case of metal-doped semiconductors, alkali metals lowered the activity, while Fe and Cr drastically enhanced the activity. 1.0 wt%Fe/TiO₂ showed the best activity of 41% aming the metal-doped semiconductors. In the case of composite semiconductors, CdS-TiO₂ showed maximum activity of 45% among all the catalysts used in experiment.