Family name Du Fay (Du Fay 
) , in all the world, is a very rare surname. The last name Du Fay is characteristic of France, where it is a very rare surname, and the United States, where it is an extremely rare surname.
| VARIANT | COUNTRY |
|---|---|
| Du Fay | France, United States |
| jean du fay French mathematician, FR (b. 1397) |
|
|
|
charles-jérôme de cisternay du fay French officer, FR (b. 1662) |
|