A semiconductor device structure is provided. The semiconductor device structure includes a substrate having a first source region, a second source region, a first drain region, and a second drain region. The semiconductor device structure includes a first gate structure over the substrate and between the first source region and the first drain region. The semiconductor device structure includes a second gate structure over the substrate and between the second source region and the second drain region. A first thickness of the first gate structure is greater than a second thickness of the second gate structure. A first gate width of the first gate structure is less than a second gate width of the second gate structure.