| San Nicolás de los Arroyos | |
| Native Name: | Partido de San Nicolás de los Arroyos |
| Settlement Type: | Department |
| Image Blank Emblem: | Municipio san nicolas logo.png |
| Blank Emblem Size: | 150 |
| Coordinates: | -33.3298°N -73.79°W |
| Subdivision Type: | Country |
| Subdivision Name: | Argentina |
| Established Title: | Established |
| Established Date: | December 31, 1778 |
| Founder: | Virrey Don Pedro de Cevallos |
| Seat Type: | Seat |
| Seat: | San Nicolás de los Arroyos |
| Leader Title: | Mayor |
| Leader Name: | Manuel Passaglia |
| Unit Pref: | Metric |
| Area Total Km2: | 1183 |
| Population Total: | 137867 |
| Population Density Km2: | auto |
| Population Demonym: | nicoleña/o |
| Postal Code Type: | Postal Code |
| Postal Code: | B2900 |
| Postal2 Code Type: | IFAM |
| Postal2 Code: | BUE117 |
| Area Code Type: | Area Code |
| Area Code: | 03461 |
| Blank Name Sec1: | Patron saint |
| Blank Info Sec1: | San Nicolás de Bari |
San Nicolás de los Arroyos Partido is the northernmost partido in Buenos Aires Province, Argentina.
The provincial subdivision has a population of about 200,000 inhabitants in an area of 1183sqkm, and its capital city is San Nicolás de los Arroyos, which is around 221km (137miles) from Buenos Aires.