Electrical resistivity of cubic Laves-phase compound CeRu2 has been measured from 3 to 300 K under the quasi-hydrostatics pressure P from 1.5 up to 8 GPa. X-ray diffraction was performed at room temperature under the pressure up to 15 GPa. Temperature dependence of electrical resistivity ρ(T) shows no anomaly at pressures below 5 GPa and resistivity decreases with increasing pressure. However, ρ(T) curves, measured under the pressure above 5.5 GPa, reveal an abrupt decrease at critical temperature Ta. This indicates that a new phase is induced by the pressure. Ta shows a large pressure dependence: ΔTa/ΔP=59.2 K/GPa. According to the X-ray data, the phase transition above 5.5 GPa is a structural-phase transition.