Method of encapsulating organic light emitting display device

In a method of encapsulating an organic light emitting display device, when a lower substrate and a encapsulating substrate are encapsulated, the encapsulating process can be simplified since a sealant coating process can be performed without a mask aligning process, thereby reducing manufacturing cost. The method comprises the steps of: preparing an encapsulating substrate for encapsulating a lower substrate on which a display unit, which includes the organic light emitting display device, is formed; forming a black mask on a region of the encapsulating substrate, which is not a sealant region, corresponding to outer regions of the display unit; and forming a sealant on the sealant region.