The ternary mixed-dimensional TiO 2 /MoS 2 / graphene-aerogel, zero-dimensional TiO 2 nanoparticles loaded on two-dimensional MoS 2 nanosheets, and TiO 2 /MoS 2 hybrid embedded into the three-dimensional (3D) graphene aerogel, was successfully prepared by self-assembly hydrothermal reduction process. The macroscopic appearance of TiO 2 / MoS 2 /graphene-aerogel is recorded using a digital camera. The microstructure of the TiO 2 /MoS 2 /graphene-aerogel with three-dimensional interconnected porous network structure was characterized by scanning electron microscope and transmission electron microscope. UV−vis absorption spectra tests show that TiO 2 /MoS 2 /graphene-aerogel possesses enhanced light absorption properties. The photocatalytic performance of TiO 2 /MoS 2 /graphene-aerogel was tested by the photoelectrochemical system, and it is verified that the photocurrent density of the as-prepared TiO 2 /MoS 2 /graphene-aerogel is greatly improved to 105 μA/cm 2 at a voltage of 0.6 V, which is approximately 10 times than of sole TiO 2 . The improved photocatalytic activity is due to the enormous specific surface area caused by the multiaperture structure of the unique 3D graphene aerogel, maximized reactive sites, good conductivity, and positive coupling effect with TiO 2 /MoS 2 heterojunction. This study indicates that TiO 2 /MoS 2 /graphene-aerogel based photocatalysts have excellent potential for photocatalytic H 2 production and photocatalytic degradation.