Abstract: The perovskite-type AgTaO₃ crystal was prepared by mild hydrothermal method and characterized by powder X-ray diffraction, scanning electron microscopy (SEM), Brunauer-Emmet-Teller surface area (BET), XPS, FTIR and UV-vis diffuse reflectance spectra (UV-vis DRS). Rietveld refinements indicated that AgTaO₃ crystallized in orthorhombic system with space group Pcmn. The results showed that the compound had high photocatalytic activity at room temperature and could degrade amaranth under UV-light irradiation effeciently.