Provided is a semiconductor device including a substrate, one hybrid fin, a gate, and a dielectric structure. The substrate includes at least two fins. The hybrid fin is disposed between the at least two fins. The gate covers portions of the at least two fins and the hybrid fin. The dielectric structure lands on the hybrid fin to divide the gate into two segment. The two segments are electrically isolated to each other by the dielectric structure and the hybrid fin. The hybrid fin includes a first portion, disposed between the two segments of the gate; and a second portion, disposed aside the first portion, wherein a top surface of the second portion is lower than a top surface of the first portion.