Bring a large pot of lightly salted water to a boil. Cook elbow macaroni in the boiling water, stirring occasionally, until cooked through but firm to the bite, 8 minutes; drain.
Combine macaroni, Cheddar cheese, ham, and mayonnaise in a 9x13 baking dish until well mixed.
Sprinkle bread crumbs over the macaroni casserole.
Bake casserole in the preheated oven until bread crumbs are lightly browned, about 25 minutes.