An environmental sensitive electronic device package includes a first substrate, a second substrate, an environmental sensitive electronic device, at least one side wall barrier structure, and a filler layer. The first substrate has at least one predetermined flexure area. The second substrate is located above the first substrate. The environmental sensitive electronic device is located on the first substrate and between the first substrate and the second substrate. The side wall barrier structure is located between the first substrate and the second substrate and surrounds the environmental sensitive electronic device. The side wall barrier structure has at least one flexure stress dispersing structure that is located in the predetermined flexure area. The filler layer is located between the first substrate and the second substrate and covers the side wall barrier structure and the environmental sensitive electronic device.