A method for fabricating a semiconductor structure includes forming a plurality of first gate structures on a first region of a substrate, a plurality of second gate structures on a second region of the substrate, and a first stress layer on both sides of each first gate structure; forming a first-region mask layer on the first stress layer; forming a second stress layer on both sides of each second gate structure; forming a contact-hole etch stop layer on the second stress layer; forming a plurality of first contact holes on the first stress layer and a plurality of second contact holes on the second stress layer to expose the contact-hole etch stop layer; at least partially removing the contact-hole etch stop layer in each first contact hole; and removing the first-region mask layer in each first contact hole and the contact-hole etch stop layer in each second contact hole.