The Kęsgailos family (plural; singular: Kęsgaila) was a Lithuanian noble family, one of the largest landowners in the Grand Duchy of Lithuania. The family descended from the  and its roots trace to the 14th century (a semi-legendary Buseika (Lithuanian sources: Buška, Polish sources: Buszka) is considered the ancestor of the family).
The Kęsgailos family, a prominent Lithuanian noble lineage, held significant landholdings within the Grand Duchy of Lithuania. Their ancestry can be traced back to the 14th century, with a semi-legendary figure named Buseika (Buška in Lithuanian sources and Buszka in Polish sources) considered their progenitor.