A package of an environmentally sensitive electronic device including a first substrate, a second substrate, an environmentally sensitive electronic device, a plurality of barrier structures, and a fill is provided. The second substrate is disposed above the first substrate. The environmentally sensitive electronic device is disposed on the first substrate and located between the first substrate and the second substrate. The barrier structures are disposed between the first substrate and the second substrate, wherein the barrier structures surround the environmental sensitive electronic device, and the water vapor transmission rate of the barrier structures is less than 10−1 g/m2/day. The fill is disposed between the first substrate and the second substrate and covers the environmentally sensitive electronic device and the barrier structures.