In March 1874, Fr. William O’Connor celebrated the first Mass in Oakdale in the Oakdale Hotel.  Beginning in 1881, Fr. Patrick Welsh, pastor of St. Stanislaus in Modesto, began to celebrate Mass monthly here and in 1888, Fr. Thomas McGuire built a small church dedicated to St. Mary.  In 1902, San Francisco Archbishop, Patrick Riordan, formally declared St. Mary’s a parish with Fr. William Nevin assigned as the first resident pastor.  St. Mary’s was also entrusted with responsibility for the missions in La Grange and Eugene. 

Following a fire in 1951 which destroyed the church on Yosemite Ave., parishioners broke ground for the present church on Oak Ave. in 1952.  The building was designed as a traditional California mission revival building with Moorish influences.  Fr. Bryan O’Rourke was named pastor and entrusted with the task of raising funds for the new church, a school and a rectory.  He served as pastor from 1952 until his retirement in 1980, during which time he was named Monsignor. 

Fr. B. Joseph Mannion was named to succeed Monsignor O’Rourke as pastor and served for 16 years, retiring in 1996.  He was instrumental in building the shrine to Our Lady of Fatima on the parish grounds which provides a quiet place for parishioners and visitors to pray.  It was also during his tenure as pastor that parishioner Roberto Magdaleno was the first from St. Mary's to be ordained as a Permanent Deacon.    Fr. (later Monsignor) Aloys Conrad Gruber succeeded Fr. Mannion as pastor and served from 1996 until his retirement in December of 2011.  Father Richard Morse, an Oblate of St. Francis de Sales, came as Administrator in July of 2011 and was named pastor in February of 2012.