Disclosed are a memory device including a vertical stack structure, a method of manufacturing the same, and/or an electronic device including the memory device. The memory device including a vertical stack structure includes an oxygen scavenger layer on a base substrate, a recording material layer on the oxygen scavenger layer and in direct contact with the oxygen scavenger layer, a channel layer on the recording material layer, a gate insulating layer on the channel layer, and a gate electrode on the gate insulating layer. The oxygen scavenger layer includes an element that forms oxygen vacancies in the recording material layer and does not include oxygen.