| Catherine | |
|---|---|
| Augusta | |
| Byzantine Empress consort | |
| Tenure | 1057–1059 |
| Spouse | Isaac I Komnenos |
| Father | Ivan Vladislav of Bulgaria |
| Mother | Maria |
Catherine of Bulgaria (Church Slavonic: Єкатерїна, Greek: Αἰκατερίνη, romanized: Aikaterini, Bulgarian: Екатерина, romanized: Ekaterina; died after 1059) was empress consort to Byzantine emperor Isaac I Komnenos and co-regent of Constantine X for a period after the abdication of her spouse in 1059. She was a daughter of Ivan Vladislav of Bulgaria and his wife Maria, and thus a sister of Presian and Alusian. Catherine was also a paternal aunt of Maria of Bulgaria.