As far back as the 1950's, the Catholic communities of South Gippsland dreamed of having a Catholic secondary college within close proximity of their towns. At that time, students seeking a Catholic secondary education were forced to attend boarding schools in Melbourne and beyond or to undertake long and tiring bus travel to schools in the Latrobe Valley.

Monsignor J. Cunningham of the Leongatha Parish had the foresight to purchase some fifty acres of land on the town boundary as the site for a future college. However, it was not until the late 1970's that the vision became a real possibility with the setting up of a working party to oversee the establishment of a Catholic secondary college serving the five parishes of Leongatha, Korumburra, Foster, Wonthaggi and San Remo.

On the first day of school in 1986, the new college opened its doors in two portable classrooms behind St Laurence’s Primary School, with sixty-six Year 7 students, three full time teachers and a new and most enthusiastic Principal, Mr Ed Carmody. The following year saw the College expand and re-establish on its present, permanent site with an old farm house as its administration and staff centre and a collection of portables as classrooms, library and central meeting place. In that year, the College was fortunate to establish a link with the Sisters of St Joseph, Mary MacKillop’s order, by securing the services of Sister Briege Buckley. Sister Briege subsequently stayed for the next nine years until her return to Ireland at the beginning of 1997.

In 1989, with the help of government funding, the first permanent buildings were erected and subsequent additions were made in 1991 and 1994. 1996 saw the official opening of the College Chapel, funded entirely by the local Parish communities. Further permanent buildings have been added in 1998 and 2001 with additional funding approved for the addition of an Arts complex, a refurbishment of the Woodwork area and additional classrooms in 2004. In 2005 Construction of a Multi-Purpose Hall has begun. This project too has been funded entirely by the local Parish communities. The result of this continued growth is that the College has modern facilities that allow students to achieve at the highest level across the broad range of curriculum areas.

In 2005 the College has grown to almost 400 students and has earned itself an enviable record of success for its students, an atmosphere of real care and concern for each student and a dedicated, well-trained professional staff. Students who graduate from Mary MacKillop Catholic Regional College are well equipped for their chosen post-school pathway be it tertiary study, vocational training or employment.

The College emblem, depicts the Cross in the background with the Holy Spirit in front, its wings segmented into five sections representing the five parishes of the region. The College motto “Sapientia Domini Docet Nos” translates as “The wisdom of the Lord teaches us”.