Abstract: Aspects of the present invention provide a proton conductive electrolyte suitable for a fuel cell material and a fuel cell including the proton conductive electrolyte. More particularly, aspects of the present invention provide a proton conductive electrolyte that has good proton conductivity and can be used to form a membrane having good flexibility. As a result, the proton conductive electrolyte can be used in a fuel cell, the electrolyte membrane of a fuel cell or the electrodes thereof, and can provide a solid polymer fuel cell having high current density, high power and long life-time in a dry environment (relative humidity of 50% or less) at an operating temperature of 100 to 200° C.