A semiconductor device and a method for manufacturing the same are disclosed. In the semiconductor device, an upper part of a storage node contact plug is increased in size, and an area of overlap between a storage node formed in a subsequent process and a storage node contact plug is increased, such that resistance of the storage node contact plug is increased and device characteristics are improved. The semiconductor device includes at least one bit line formed over a semiconductor substrate, a first storage node contact plug formed between the bit lines and coupled to an upper part of the semiconductor substrate, and a second storage node contact plug formed over the first storage node contact plug, wherein a width of a lower part of the second storage node contact plug is larger than a width of an upper part thereof.