A 2D/2D MXene/TiO₂-MoS₂ heterostructure was fabricated via wet etching. The structure was characterized using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and high-resolution transmission electron microscopy (HRTEM). And the electrochemical properties of the heterostructure were investigated as well. It is found that wet-etching yields few layer of 2D MXene nanosheets, which could provide a larger surface area for the growth of ultrathin 2D MoS₂ nanosheets. The MoS₂ nanosheets tend to grow vertically on the MXene nanosheets, thereby offering a greater surface area and more exposed active sites. Some MXene nanosheets are in-situ derived into TiO₂ nanoparticles, forming a rich heterogeneous interface between MXene, TiO₂ and MoS₂. And these interfaces modulate the electronic structure of the heterostructure, effectively improving its charge transfer efficiency, thereby improving the catalytic activity and stability of the material. The 2D/2D MXene/TiO₂-MoS₂ heterostructure exhibits remarkable oxygen evolution reaction (OER) performance, with an overpotential of only 376 mV at a current density of 50 mA/cm². After a 40 h constant voltage stability test, the voltage retention rate reaches 99.2%.