Photocatalysis is one of the most promising technologies for solar energy conversion. With the development of photocatalysis technology, the creation of low-dimensional structure photocatalysts with improved properties becomes more and more important. Metallic 1T-TiS2 nanodots with a low-dimensional structure were introduced into environmentally friendly two-dimensional g-C3N4 (2D-C3N4) nanosheets by a solvothermal method. It was found that the ultrathin TiS2 nanodots were uniformly anchored on the surface of the 2D-C3N4. The effective suppression of electron–hole recombination was realized due to the addition of the intrinsic metallic property of 1T-TiS2 in the prepared nanocomposite. The 5 wt% TiS2/2D-C3N4 nanocomposite exhibited the best photocatalytic performance and the degradation rate towards RhB was ca. 95% in 70 min, which showed an improvement of ca. 30% in comparison with 2D-C3N4. The results indicate that the obtained TiS2/2D-C3N4 nanocomposite is a promising photocatalyst for practical applications.