Semiconductor device

A semiconductor device includes a first active pattern on a substrate, the first active pattern extending in a third direction having an acute angle with respect to a first direction and a second direction, the first direction and the second direction being substantially parallel to an upper surface of the substrate and substantially perpendicular to each other, a first conductive filling pattern on an upper surface of a central portion of the first active pattern, the first conductive filling pattern having a shape of a parallelogram, a gate structure extending in the first direction in an upper portion of the first active pattern, and a bit line structure on the first conductive filling pattern and extending in the second direction.