A non-volatile memory device includes gate structures, an insulation layer pattern, and an isolation structure. Multiple gate structures being spaced apart from each other in a first direction are formed on a substrate. Ones of the gate structures extend in a second direction that is substantially perpendicular to the first direction. The substrate includes active regions and field regions alternately and repeatedly formed in the second direction. The insulation layer pattern is formed between the gate structures and has a second air gap therein. Each of the isolation structures extending in the first direction and having a first air gap between the gate structures, the insulation layer pattern, and the isolation structure is formed on the substrate in each field region.