A semiconductor device includes: a substrate having active regions defined by a device isolation region; a conductive line extending in a direction on the active regions; insulating liners on both sidewalls of a lower portion of the conductive line that contacts with the active regions; spacers that are apart from the insulating liners in a direction perpendicular to a surface of the substrate and sequentially formed on both sidewalls of an upper portion of the conductive line; a blocking layer arranged at a spacing between a spacer located in the middle of the spacers and the insulating liners and in a recess portion recessed from one end of the spacer located in the middle of the spacers toward the conductive line; and conductive patterns arranged on the active regions on both sides of the spacers.