| Sventsyany uezd | |
| Native Name: | Свѣнцянскій уѣздъ |
| Native Name Lang: | ru |
| Settlement Type: | Uezd |
| Mapsize: | 225px |
| Subdivision Type: | Country |
| Subdivision Name: | Russian Empire |
| Subdivision Type1: | Krai |
| Subdivision Name1: | Northwestern |
| Subdivision Type2: | Governorate |
| Subdivision Name2: | Vilna |
| Established Title: | Established |
| Established Date: | 1795 |
| Extinct Title: | Abolished |
| Extinct Date: | 1920 |
| Seat Type: | Capital |
| Seat: | Sventsyany |
| Area Total Km2: | 5,228.03 |
| Population As Of: | 1897 |
| Population Total: | 172,231 |
| Population Density Km2: | auto |
| Population Urban: | 3.50% |
| Population Rural: | 96.50% |
| Total Type: | Total |
The Sventsyany uezd, known until 1842 as the Zavileisky uezd, was a county (uezd) of the Vilna Governorate of the Russian Empire.
The uezd was bordered by the Vilna uezd to the west, the Oshmyany uezd to the south, the Vileyka uezd to the east, the Disna uezd to the northeast, and the Novoaleksandrovsk uezd of the Kovno Governorate to the north. The administrative centre was located in Sventsyany (modern-day Švenčionys). The Sventsyany uezd included the most part of Švenčionys District and Pastavy District of Belarus.
At the time of the Russian Empire Census of 1897, Sventsyansky Uyezd had a population of 172,231. Of these, 47.5% spoke Belarusian, 33.8% Lithuanian, 7.1% Yiddish, 6.0% Polish, 5.4% Russian and 0.1% German as their native language.[1]