| Svitiaz | |
| Location: | Shatsk National Natural Park, Kovel Raion, Volyn Oblast |
| Group: | Shatsky Lakes |
| Coords: | 51.5°N 69°W |
| Pushpin Map: | Ukraine#Ukraine Volyn Oblast |
| Pushpin Map Alt: | Location of a lake in Ukraine |
| Basin Countries: | Ukraine |
| Length: | 9.3km (05.8miles) |
| Width: | 8km (05miles) |
| Area: | 25.2km2 |
| Depth: | 6.9m (22.6feet) |
| Max-Depth: | 58.4m (191.6feet) |
| Volume: | 180e6m3 |
| Islands: | 1 (7disp=orNaNdisp=or) |
Svitiaz (Ukrainian: Світязь, pronounced as /uk/; Belarusian: Свіцязь; Polish: Świtaź; Russian: Свитязь) is a lake in the Ukrainian oblast of Volyn. It is the deepest and second largest lake in Ukraine, with a maximum depth of 58.4 meters and an area of 25.2 km2, and is a popular tourist site in the summer. The lake is one of the Shatsk Lakes of the Shatsk National Natural Park, located in the Kovel Raion of northwestern Ukraine.
The lake has a length of 9.3 km, a maximum width of 8 km, a volume of 0.185 km3, and an average depth of 6.9 meters, with an island in the middle with an area of 7 hectares.