The invention provides a memory device. The memory device includes a substrate, a plurality of first wires, a plurality of etch-stop layers, a dielectric layer, and a plurality of vias. The substrate has a plurality of first regions and a plurality of second regions arranged in a staggered manner along a first direction. The first wires are embedded in the substrate and extended along the first direction. The first wires include a conductive layer and a cap layer located on the conductive layer, and the upper surface of the cap layer has a groove. The etch-stop layers are located on the cap layer and filled in the groove. The dielectric layer is located on the substrate and has a plurality of via openings in the first regions. The via openings expose the substrate and the etch-stop layer. The vias are filled in the via openings and electrically connected to the substrate. The invention further provides a manufacturing method of a memory device.