Kosciuška is the masculine form of a Lithuanian family name. Its feminine forms are: Kosciuškienė (married woman or widow) and Kosciuškaitė (unmarried woman).
Notable people with the surname include:
Tadas Kosciuška (1765-1794), Lithuanian name of Tadeusz Kościuszko Vaclovas Kosciuška (1911-1984), Lithuanian painter and graphic designer