| Tunuyán | |
| Native Name: | Departamento Tunuyán |
| Settlement Type: | Department |
| Coordinates: | -33.5689°N -69.0264°W |
| Subdivision Type: | Country |
| Subdivision Name: | Argentina |
| Established Title: | Established |
| Established Date: | November 25, 1880 |
| Founder: | ? |
| Seat Type: | Seat |
| Seat: | Tunuyán |
| Leader Title: | Mayor |
| Leader Name: | Emir Andraos, PJ |
| Unit Pref: | Metric |
| Area Total Km2: | 3,317 |
| Population Total: | 42,125 |
| Population Density Km2: | auto |
| Population Demonym: | tunuyanense |
| Postal Code Type: | Postal Code |
| Postal Code: | M5560 |
| Postal2 Code Type: | IFAM |
| Postal2 Code: | MZA017 |
| Area Code Type: | Area Code |
| Area Code: | 02622 |
| Blank Name Sec1: | Patron saint |
| Blank Info Sec1: | ? |
Tunuyán Department is a department located on the eastern border of Mendoza Province in Argentina.
The provincial subdivision has a population of about 42,000 inhabitants in an area of, and its capital city is Tunuyán, which is located around from the Capital Federal.