Two kinds of hybrid metal oxide quantum dots, Cu_xO and Fe_xO, were successfully anchored on TiO₂ blocks by a facile, low-cost and large scale reflux method. The resultant photocatalysts (Cu_xO/TiO₂ and Fe_xO/TiO₂) were characterized by transmission electron microscope (TEM), Brunauer-Emmett-Teller (BET), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and UV-vis absorption spectrum, and their photocatalytic performances were evaluated by photocatalytic decoloration of methylene blue (MB) solution under simulated sunlight and visible light (λ > 420 nm) irradiation. The results showed that hybrid metal oxide quantum dots Cu_xO (or Fe_xO) were dispersed uniformly on TiO₂ blocks. Both Cu and Fe are in mixed valences state (Cu⁺ and Cu²⁺, Fe²⁺ and Fe³⁺, respectively). Cu_xO/TiO₂ and Fe_xO/TiO₂ demonstrated high photocatalytic ability whether they were under simulated sunlight or under visible light (λ > 420 nm) irradiation, which can be confirmed from the measurement of the amount of hydroxyl radicals (•OH). Based on the above results, the mechanisms of enhanced photocatalysis on Cu_xO/TiO₂ and Fe_xO/TiO₂ under simulated sunlight and visible light were proposed.