Abstract: Provided are titanium oxynitride having a titanium deficiency-type halite structure (Ti1-xO1-yNy, wherein x and y are real numbers), in which x representing a deficiency degree of titanium is greater than 0 and less than 1, and y representing an introduction degree of nitrogen is greater than 0 and less than 1, and a method of preparing the same. The titanium oxynitride having the titanium deficiency-type halite structure with an improved photocatalyst property in the visible wavelength region may be provided.