Diego de Arce y Reinoso Ávila y Palomares was a Spanish bishop who served as Grand Inquisitor of Spain from 1643 to 1665; and as Bishop of Plasencia (1640–1652), Bishop of Ávila (1637–1640), and Bishop of Tui (1635–1637).

The Diocese of Plasencia is a suffragan Latin diocese of the Catholic Church in the ecclesiastical province of the Metropolitan Archbishop of Mérida-Badajoz, in Extremadura, western Spain.