Most Reverend Gregory L. Parkes serves as fifth bishop of the Diocese of St. Petersburg.

Pope Francis appointed Bishop Parkes to be shepherd of the Diocese of St. Petersburg on November 28, 2016, and his Installation Mass was celebrated on January 4, 2017, at the Cathedral of St. Jude the Apostle in St. Petersburg.  He succeeded Bishop Robert Lynch who retired at the age of 75 and is serving as Bishop Emeritus of the Diocese of St. Petersburg.

Bishop Parkes was ordained to the episcopacy and installed as the fifth bishop of the Diocese of Pensacola-Tallahassee on Tuesday, June 5, 2012, at St. Paul Catholic Church in Pensacola. Archbishop Thomas Wenski was principal consecrator at the Ordination Mass.

He was ordained a priest of the Diocese of Orlando by Bishop Norbert Dorsey on June 26, 1999.

His assignments after ordination have included parochial vicar at Holy Family Catholic Church in Orlando and founding pastor of Corpus Christi Catholic Church in Celebration. Bishop Parkes served the Diocese of Orlando as Vicar General and Chancellor for Canonical Affairs while also serving as pastor of Corpus Christi Parish.