Barbara of Cilli (1392 – July 11, 1451) is the spouse of Holy Roman Emperor Sigismund and as such Holy Roman Empress.

She is by marriage also Queen of Hungary and Bohemia.

She is actively involved in politics and economy of her times, independently administering large feudal fiefdoms and taxes, and is instrumental in creating famous royal Order of the Dragon.

She serves as the regent of the Hungarian kingdom in the absence of her husband.

Barbara wis the daughter of Herman II, Count of Celje, and Countess Anna of Schaunberg.