A lateral diffused metal oxide semiconductor (LDMOS) device includes a first fin-shaped structure on a substrate, a second fin-shaped structure adjacent to the first fin-shaped structure, a shallow trench isolation (STI) between the first fin-shaped structure and the second fin-shaped structure, a first gate structure on the first fin-shaped structure, a second gate structure on the second fin-shaped structure, and an air gap between the first gate structure and the second gate structure.