A hermetic encapsulation package and a method of fabricating such package, wherein at least one organic electroluminescent (EL) element is formed on a support substrate. A sealing cap for accommodating the organic EL element is bonded to the support substrate with an ultraviolet curing resin to form a sealed space defined by the sealing cap and the support substrate. At least part of the sealing cap is formed of an elastic material of a Young's modulus of 70 GPa or less. The elastic portion of the sealing cap is reversibly deflected to provide a decrease or increase in the volume of the sealed space to reduce pressure changes inside the sealed space caused by changes in temperature, thereby alleviating problems of thermal shock.