Euphemia (Greek: Εὐφημία; ´well-spoken [of]´), known as the All-praised in the Eastern Orthodox Church, was a virgin martyr, who died for her faith at Chalcedon in 303 AD.
According to tradition, Euphemia was martyred for refusing to offer sacrifices to Ares. She was arrested and after suffering various tortures, died in the arena at Chalcedon from a wound sustained from a bear. Her tomb became a site of pilgrimages. She is commemorated on September 16.