TiNx thin films were deposited on p-Si(111) substrate by DC magnetron reactive sputtering method. The composition, structure and photoelectric properties of the films were studied by using energy dispersive x-ray spectroscopy (EDX), x-ray diffraction (XRD), UV-visible spectrophotometer, and four-probe resistivity meter. The results show that the atomic ratio N/Ti of the prepared TiNx thin films is close to 1. The preferred orientation of TiNx thin films is obviously influenced by the substrate temperature and there is a transition of the preferred orientation from (111) to (200) when the substrate temperature is about 240℃. The average reflectivity of the films in the near infrared band first increases and then decreases with the increase of the substrate temperature, while the resistivity of TiNx thin films decreases rapidly.