The suppression of the recombination of electrons and holes (e–h) and the enhancement of the light absorption of semiconductors are two key points toward efficient photocatalytic degradation. Here, we report a few-layer g-C 3 N 4 / α-MoO 3 nanoneedles (flg-C 3 N 4 / α-MoO 3 NNs) all-solid-state Z-scheme mecha- nism photocatalyst synthesized via a typical hydrothermal method in a controlled manner. The recom- bination of the photo-induced e–h pairs could be effectively restrained by the Z-scheme passageway be- tween the flg-C 3 N 4 and α-MoO 3 NNs in the composite, which could also promise a high redox ability to degrade pollutants. And it became possible for the prepared photocatalyst to absorb light in a wide range of wavelengths. The detailed mechanism was studied by electron spin-resonance spectroscopy (ESR). The low-dimensional nanostructure of the two constituents ( α-MoO 3 NNs with one-dimensional structure and flg-C 3 N 4 with two-dimensional structure) endowed the composite with varieties of excellent physic- ochemical properties, which facilitated the transfer and diffusion of the photoelectrons and increased the specific surface area and the active sites. The 10 wt％ flg-C 3 N 4 / α-MoO 3 NNs showed the best photocat- alytic performance toward RhB degradation, the rate of which was 71.86％, ～2.6 times higher than that of α-MoO 3 NNs.