Pressure-temperature phase diagram of CeNiGe 3 is reinvestigated with electrical resistivity measurement up to p ∼ 4 GPa utilizing a single crystal under the better hydrostatic condition. We discovered that the new successive phase transition appears above p ∼ 3.7 GPa in the antiferromagnetic phase (AFM-I), and the superconductivity disappears simultaneously. The application of magnetic field along the a-axis suppresses the successive transition, indicating that the new pressure-induced phase is considered as an antiferromagnetic phase (AFM-II) with a small magnetization compared with that of the AFM-I phase. We found that the ordered state in the AFM-II phase is conclusively different from the commensurate AFM-I state which was observed in the previous nuclear-quadrupoleresonance study, and the superconductivity can coexist with the commensurate AFM-I state, but not with the AFM-II state.