Annia Galeria Faustina, more familiarly referred to as Faustina I (Latin: Faustina Major; born on September 21, in about 100; died in October or November of 140), was a Roman Empress and wife of Roman Emperor Antoninus Pius.

Faustina was the only known daughter of consul and prefect Marcus Annius Verus and Rupilia Faustina. Her brothers were consul Marcus Annius Libo and praetor Marcus Annius Verus. Her maternal aunts were Roman Empress Vibia Sabina and Matidia Minor. Her paternal grandfather had the same name as her father and her maternal grandparents were Salonina Matidia (niece of Roman Emperor Trajan) and suffect consul Lucius Scribonius Libo Rupilius Frugi Bonus. Faustina was born and raised in Rome.

As a private citizen, she married Antoninus Pius between 110 and 115. Faustina and Antoninus had a very happy marriage. Faustina bore Antoninus four children, two sons and two daughters. They were:

On July 10, 138, her uncle, Emperor Hadrian, died and her husband became the new emperor, as Antoninus was Hadrian's adopted son and heir. Faustina became Roman Empress and the Senate accorded her the title of Augusta. As empress, Faustina was well respected and was renowned for her beauty and wisdom. The Augustan History criticized her as having "excessive frankness" and "levity". Throughout her life, as a private citizen and as empress, Faustina was involved in assisting charities for the poor and sponsoring and assisting in the education of Roman children, particularly girls.