In 1905, a small group of Sisters of Mercy came from Wentworth to Mildura and established a convent in a weatherboard building on the corner of Pine Avenue and Tenth Street.
Catholic secondary education commenced in Mildura in 1906 when the Sisters of Mercy began conducting classes in rooms attached to the original convent in Pine Avenue. The Certificate of Registration of a School dated 31st December, 1906, indicates that sub‐primary, primary and secondary classes were being conducted from convent at the time.
In 1911 boarding school facilities were provided in Olive Avenue and in 1914 a new school was erected in Walnut Avenue. The first buildings of St Joseph's College at its present site were opened in 1929. The College has well equipped classrooms, science and computer laboratories, creative arts and design and technology complex, religious education centre, library, sports facilities, staff and student amenities.
Major building projects include:
Administration: Original offices opened 1979. Refurbished to include staff areas, officially blessed May 17 1996. Minor refurbishment was undertaken prior to the commencement of the 2009 school year.
Library: Initial library built 1979. Relocated to new 'Haenen Library' on site of original classrooms March 20 1988.
Creative Arts: Complex opened as 'John Howden Centre' 1984. Refurbished to include Technology and Sports facilities 2002.
McAuley Wing: New classrooms, officially opened 1992 and refurbished to commence the 2009 school year. Nearby portable classrooms were included in this refurbishment.
Langtree Park: Classrooms, Careers, VCE Study and offices. Officially opened 2000.
Mercy Centre: Sisters relocated to 177 Twelfth St. Convent refurbished to include Textiles, Home Economics, LOTE and meeting areas. Official blessing and opening December 7 2003. Science classrooms refurbished at this time.
Church: Original Mildura Catholic Church relocated and reconsecrated as St Paul's Primary School Chapel during Mercy Centenary celebrations March 2005.
Chapel: Refurbished and housing the Sisters of Mercy Centenary Sculpture. The chapel was re-opened during the Centenary.
Stadium: St Joseph's College Stadium was purchased in 2005. Redeveloped during 2008 to include a theatre and dance studio as well as classrooms. Official Blessing and Opening took place on 20 October, 2008.