| Castellazzo Bormida | |
| Official Name: | Comune di Castellazzo Bormida |
| Coordinates: | 44.845°N 8.5775°W |
| Region: | Piedmont |
| Province: | Alessandria (AL) |
| Frazioni: | Fontanasse |
| Area Total Km2: | 45.13 |
| Population Footnotes: | [1] |
| Population Total: | 4526 |
| Population As Of: | 31 August 2017 |
| Population Demonym: | Castellazzesi |
| Elevation M: | 104 |
| Postal Code: | 15073 |
| Area Code: | 0131 |
Castellazzo Bormida (Ël Castlass in Piedmontese, and Castlass an Burmia or Castlas an Burmia locally) is a comune (municipality) in the Province of Alessandria in the Italian region Piedmont, located about 70km (40miles) southeast of Turin and about 8km (05miles) southwest of Alessandria.
Castellazzo Bormida borders the following municipalities: Alessandria, Borgoratto Alessandrino, Casal Cermelli, Castelspina, Frascaro, Frugarolo, Gamalero, Oviglio, and Predosa.