Founded in 1917, the school is one of the oldest in Papua New Guinea and is located next to St Joseph's Parish Church.

Originally situated within the Convent of the Daughters of Our Lady of the Sacred Heart (OLSH) behind St. Mary's Cathedral, it started with only 15 pupils.

Enrollments rose steadily after the war and by the late 1950s the school's facilities had become too small to cater for the children's needs.

The relocation took several years and was done in stages, starting with one class moving from Port Moresby to the Church Hall in Boroko in 1957.

[6]: 3  [7]: 2  An inter-school rugby union competition for the National Capital District was started in 2013, with St Joseph's fielding teams in the grand final matches of all three divisions – U14 and U17 male, and U17 female.