- Source: Ustariz
Ustariz is a surname. Notable people with the surname include:
Juan Andrés de Ustariz (1656–1718), Royal Governor of Chile
Mariano Eduardo de Rivero y Ustariz (1798– 857), Peruvian scientist
Miguel Antonio de Ustáriz (died 1792), governor of Puerto Rico
Rosario Ustáriz Borra (1927–2009), Spanish writer and poet