Police say the man was visiting a museum in Florence last weekend, when he tried to measure his own finger against the finger on a statue of the Virgin Mary by medieval sculptor Giovanni d'Ambrogio.
That's when the finger broke off.
The museum has signs reminding visitors not to touch the artwork.
Officials are confident the finger can be restored. It was made of plaster.
Police have not identified the man but say he is from Connecticut and works as a surgeon.