Solution method is a mild, controllable and commonly used synthetic method. However, the reported solution methods for the preparation of TiSe₂ nanosheets usually use trioctylphosphine (TOP) as solvent. TOP is poisonous and potentially harmful to the human body as well as the environment. In this paper, hexagonal TiSe₂ nanosheets were synthesized by simple solution method without TOP. The shape evolution of TiSe₂ nanosheets was investigated by adjusting the reaction time. The crystal phase, morphology, elements, and the optical property of TiSe₂ nanosheets were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), and UV-Vis spectroscopy, respectively. The spiral growth steps can be clearly observed in SEM images. A spiral layer by layer growth mechanism was proposed based on the morphology evolution of TiSe₂ nanosheets. The photocatalytic activity of TiSe₂ nanosheets was evaluated by the degradation of RhB under sun light irradiation. Compared with the commercial P25, the as-prepared TiSe₂ nanosheets exhibit a superior photocatalytic activity, which indicates that TiSe₂ nanosheets are promising candidate as photocatalytic material for environmental protection.