The Pejačević or Pejácsevich family (Croatian: Pejačevići, Hungarian: Pejácsevich) is an old Croatian noble family, remarkable during the period in history marked by the Ottoman war in the Kingdom of Croatia and Austro-Hungarian Empire respectively. Notable members of the family were politicians, clerics, artists, senior military officers, bans (viceroys) of Croatia and other high state officials. They were very potent and influential in the political, social, economic and cultural life of the country, and especially distinguished in the region of Slavonia. In German, the family name was sometimes rendered Pejacsevich, i.e. a simplified variant of the Hungarian spelling.
The origin of the family dates back to the 14th-century territory of southeastern Croatia and the neighboring medieval Bosnia and Herzegovina. There are sources that connect the ancestors of the family with the Bosnian king Stjepan Dabiša (English: Stephen Dabisha), who ruled from 1391 to 1395, and his son Parčija (English: Parchia). Parčija's descendants used to be called Parčević (Parchevich). One of several family branches that came out of them later (in the 16th century) was the Pejačević family.