The invention discloses a memory structure forming method. The method comprises steps: a substrate comprising a device area and a peripheral area is provided; a plurality of gate structures extending from the device area to the surface of the peripheral area are formed on the surface of the substrate, the gate structures cross the surfaces of a plurality of active areas, and two sides of the gate structures are provided with source area channels and drain area channels; a first dielectric layer is formed on the surface of the substrate; a source area interconnection line is formed in the source area channel of the device area; a second dielectric layer is formed on the surfaces of the source area interconnection lines, the first dielectric layer and the gate structures; a plurality of first through holes are formed in the second dielectric layer; third barrier layers are formed on the surfaces of the side walls of the first through holes; a first barrier layer and the first dielectric layer at the bottom part of the first through hole of the peripheral area are removed to form a control gate through hole and a drain area through hole; and a drain area plug is formed in each drain area through hole, and a control gate plug is formed in each control gate through hole. The formed memory structure has the advantages of good appearance, stable performance and improved reliability.