The Diocese of Guiratinga (Dioecesis Guiratingensis) was a former ecclesiastical circumscription of the Catholic Church in Brazil, belonging to the Ecclesiastical Province of Cuiabá and the West II Regional Bishops' Council of the National Conference of Bishops of Brazil, being a suffragan of the Archdiocese of Cuiabá.

The episcopal see is the Cathedral St. John the Baptist in the city of Guiratinga in the state of Mato Grosso.

The Prelature Registry Araguaia (Territorialis Praelatura Registrensis or Territorialis Praelatura registration Araguaia) was erected on May 12, 1914, by Pope Pius X, by decree of the Sacred Congregation Concistorial [1], from territory taken from the Archdiocese Cuiabá, and delivered by the Holy See to the care of the Salesians.

1st Bishop Prelate: Don Antonio Malan - SDB - (1914-1924) Apostolic Administrator: Mons.

On October 3, 1981, it was promoted to the rank of diocese by Pope John Paul II.