In situ high-pressure energy dispersive x-ray diffraction experiments on polycrystalline powder TiN with NaC1type structure have been conducted with the pressure up to 30.1 GPa by using a diamond anvil cell instrument with synchrotron radiation at room temperature. The experimental results suggest that an isostructural phase transition might exist at about 7GPa as revealed by the discontinuity of V/Vo with pressure.