| Native Name: | Georgian: ქსნის საერისთავო |
| Conventional Long Name: | Duchy of Ksani |
| Common Name: | Ksani |
| Subdivision: | Principality |
| Nation: | the Kingdom of Kartli |
| Era: | Middle Ages |
| Capital: | Kvenipnevi |
| Coordinates: | 42.1194°N 44.4878°W |
| Image Map Caption: | The duchy as in the 17th and 18th centuries |
| Life Span: | 15th century-1801 |
| Year Start: | 15th century |
| Year End: | 1801 |
The Duchy of Ksani (Georgian: ქსნის საერისთავო) was an administrative unit in feudal Georgia. It consisted lands around Ksani and two more neighbouring south-western valleys, thus making two administrative entities: Ksniskhevi, with its centre in Kvenipnevi and Tskhradzmiskhevi with its centre in Largvisi, which is also home of the Largvisi Monastery.
Tskhradzmiskhevi started to become dominant in the 10th century when it included gorges of Lekhura, Medjuda and upper side of the river Liakhvi. After incorporating of neighbouring southern gorges, the residence was relocated from Largvisi to Kvenipnevi.
According to Vakhushti's references, during the reign of Tamar the Great, Kartli and Ksani were separated Dukedoms. After the Mongol invasion in the second half of the 13th century, the dukes of Ksani were of the Bibiluri family.
In the 14th century, Saeristavo included: Tskhradzma, Jamuri, Kharchokhi, Jurta, Kholoti, Isroliskhevi, Abazasdzeta, Truso, Ghuda, Gagasdzeni, Mleta, Arakhveti, Khando, Khanchaeti, Dzagnakora, Dighuami, Gavasi, Atseriskhevi, Bekhushe.
In the 15th century, the Saeristavo practically became a Satavado ("manorial").