Photoelectrochemical (PEC) water splitting into hydrogen and oxygen using hybridized semiconductor photoelectrodes has become a promising strategy for converting solar energy into clean and sustainable H-2 fuel. Here, we report a promising hybrid photoanode constructed by electrodepositing an amorphous Co-Pi film onto semiconducting CdSe/TiO2 nanowire arrays for photoelectrochemical hydrogen production. This photoanode exhibits a high water-splitting photocurrent density, which is attributed to the broad visible light absorption and efficient charge carrier separation by the virtue of the type-II heterojunction formed between TiO2 and CdSe. Photoconversion efficiency of Co-Pi/CdSe/TiO2 and CdSe/TiO2 photoanodes increase by 3.3 and 2.1 times, compared with the pristine TiO2 photoanode. Moreover, Co-Pi/CdSe/TiO2 photoelectrode shows greatly improved PEC stability, the drop in photocurrent of Co-Pi/CdSe/TiO2 nanowire arrays photoelectrode is about 10% after 1h illumination, because of the addition of the Co-Pi film protecting the light absorber CdSe/TiO2 from photocorrosion. The enhanced PEC performance mechanism of triple hybrid photoanode is also discussed in this paper.