Bring a large pot of lightly salted water to a boil. Add the ziti pasta, and cook for 8 minutes, or until tender. Drain.
Meanwhile, heat the oil in a small skillet over medium-high heat. Fry the ham in the oil until browned, stirring constantly. Remove from the heat and set aside. When the pasta is done and drained, mix in the ham and Swiss cheese until cheese is melted.