Barry was ordained a priest by Bishop Michael Comerford in Ireland for the Diocese of St. Augustine on June 9, 1895.[4] After his ordination, Barry immigrated to Florida, where he was appointed as a curate at Immaculate Conception Parish in Jacksonville.[5] He later worked as a chaplain for the US Armed Forces during the Spanish–American War.[3] After the war, Barry served as pastor of St. Monica's Parish in Palatka, Florida (1903–1913), and then as rector of St. Augustine's Cathedral and as vicar general of the diocese (1917–1921).[5]
In 1931, Barry instituted an annual pilgrimage to the shrine of Nuestra Señora de la Leche at the Mission Nombre de Dios in St. Augustine in order to draw attention to the heritage of the Catholic Church in St. Augustine. In June 1932, Barry went with Cardinal Patrick Hayes to attend the World Eucharistic Congress in Dublin, Ireland. In 1940, Barry founded Barry University in Miami Shores along with his sister, Mother M. Gerald Barry, and his brother, Father William Barry.[6]
Patrick Barry died from heart disease at St. Vincent's Hospital in Jacksonville, on August 12, 1940, at age 71.[5]