A vertical fin field effect transistor (V-FinFET) is provided as follows. A T-shaped fin structure extend vertically from an upper surface of a substrate. The T-shaped fin structure includes a lower part and an upper part. The lower part is in contact with the upper surface of the substrate. The upper part of the T-shaped fin structure is vertically stacked on the lower part of the T-shaped fin structure. A gate insulating layer surrounds the lower part. A work-function-control pattern surrounds the lower part. The gate insulating layer is interposed between the work-function-control pattern and the lower part of the T-shaped fin structure. A gate electrode is disposed on a sidewall of the work-function-control pattern.