A method of manufacturing a variable memory device includes forming a switching layer on a first conductive layer, forming a heating layer on the switching layer, the heating layer extending in a first direction, performing a first patterning process on the first conductive layer, the switching layer, and the heating layer to form a first trench extending in a second direction intersecting the first direction, forming variable resistance patterns on the heating layer, forming a second conductive layer on the variable resistance patterns, and performing a second patterning process on the switching layer, the heating layer, and the second conductive layer to form a second trench extending in the first direction and being between the variable resistance patterns.