Abstract: As a new type of two-dimensional nanomaterial, metal carbide/nitride nanosheets (MXene) exhibits high specific surface area and electrical conductivity, and the composition, layers and thickness of that were flexibly controllable. Mxene materials have great potential applications in energy storage, catalysis, sensing and optics. The nonlinear optical effect and response mechanism of one kind of MXene material, namely Ti3C2TX nanosheets dispersion liquid were studied. It was found that the Ti3C2TX nanosheets dispersion liquid exhibited excellent optical limiting properties for nanosecond pulse laser with 532 nm and 1 064 nm wavelength, and the limiting thresholds were estimated to be 0.14 J/cm2 and 0.12 J/cm2, respectively. By measuring the dependence of nonlinear optical scattering signals on incident light power density, it was found that the optical limiting response of the material mainly originated from the nonlinear scattering effect. Compared with the traditional optical limiting material of C60, the material has the advantages of low optical limiting threshold and wide response wavelength range.