This study investigated the effect of adding Pt components to V-TiO2 for highly concentrated ammonia photodecomposition. Pt components were introduced to the V-TiO2 photocatalysts by using two method types: the common sol-gel (Pt-V-TiO2) and impregnation (Pt/V-TiO2) methods. The observed X-ray diffraction (XRD) peaks were assigned to V2O5 at 19.5, 27.5 and 30.20 ° in V-TiO2, and to Pt metals at 39.80 ° (111) in Pt/V-TiO2. The Pt component of Pt-V-TiO2 was identified as Pt2+ from the Pt4f7/2 and Pt4f5/2 bands at 73.6 and 77.4 eV in XPS bands, respectively, but the band was shifted to a lower binding energy in Pt/V-TiO2. The H2 temperature-programmed reduction (TPR) curves showed that the temperature of reduction from Ti3+ to Ti0 was decreased by Pt addition and that the area was larger in Pt-V-TiO2 than in Pt/V-TiO2. The NH3 decomposition was slightly increased with vanadium addition compared to that of pure TiO2, and the decomposition was further enhanced with Pt addition. Particularly, the NH3 (1,000 ppm) decomposition reached 100% over Pt/V-TiO2 after 120 min, although about 10-30% of the ammonia was converted into undesirable NO2 and NO.