; Bishops of Piauí •
Joaquim Antônio d’Almeida (1905.12.14 – 1910.10.23) •
Quintino Rodrigues de Oliveira e Silva (2013.02.17, did not take effect) •
Octaviano Pereira de Albuquerque (1914.04.02 – 1922.10.27), appointed Archbishop of São Luís do Maranhão • Severino Vieira de Melo (1923.06.08 – 1944.12.16) ; Bishops of Teresina • Severino Vieira de Melo (1944.12.16 – 1952.08.09) ; Archbishops of Teresina •
Severino Vieira de Melo (1952.08.09 – 1955.05.27) •
Avelar Brandão Vilela (1955.11.05 – 1971.03.25), appointed Archbishop of São Salvador da Bahia (Cardinal in 1973) •
José Freire Falcão (1971.11.25 – 1984.02.15), appointed Archbishop of Brasília, Distrito Federal (Cardinal in 1988) •
Miguel Fenelon Câmara Filho (1984.10.07 – 2001.02.21) •
Celso José Pinto da Silva (2001.02.21 – 2008.09.03) •
Sérgio da Rocha (2008.09.03 – 15 June 2011), appointed Archbishop of Brasília, Distrito Federal (Cardinal in 2016) •
Jacinto Furtado de Brito Sobrinho (22 February 2012 – 4 January 2023) •
Juarez Sousa da Silva (4 January 2023 – present)
Coadjutor bishops •
Sérgio da Rocha (2007-2008); future Cardinal
Auxiliary bishops •
Raimundo de Castro e Silva (1950-1954), appointed Bishop of Oeiras •
José Gonzalez Alonso (1994-2001), appointed Bishop of Cajazeiras, Paraíba
Other priests of this diocese who became bishop •
Júlio César Souza de Jesus, appointed Auxiliary Bishop of Fortaleza, Ceara in 2018 ==Suffragan dioceses==