Pressure-composition isotherm and X-ray diffraction studies of ErFe2-H system have been carried out to resolve the reported controversies regarding the composition limits of various hydride phases. Further, the existence of a new plateau in ErFe2Hx for x values between 4 and 5 has been established and the structure of the new hydride phase with x similar or equal to 5 is found to be orthorhombic.