Patrick Ambrose Treacy CFC (31 August 1834 – 2 October 1912) was a Roman Catholic educationist who established the first permanent Christian Brothers community in Australia in 1868.

Treacy was sent as leader of the Christian Brothers, together with three confrères Dominic Fursey Bodkin, John Barnabas Lynch and Patrick James Nolan, who arrived in Melbourne in the Donald McKay in November 1868 to find the Catholic school system receiving some state aid, but in a parlous condition under the control of local parish priests.

Having observed the deplorable state of diocesan schools during his collecting tours, Treacy advocated to the Catholic Education Committee a rise in teachers' salaries and a training college.

Treacy's report on the condition of the system resulted in up-to-date equipment, and under him the Brothers organised a training scheme for their aspirants.

Small classes at Victoria Parade College and St Patrick's, Ballarat, taught by Brothers Nugent and Kennedy respectively, achieved eminent success in these examinations.

At this time there were no Irish secondary schools; it was Treacy's initiative and dedication that shaped the pattern of the Australian Christian Brothers' higher education without regard to pupils' social or financial standing.

Gifted with great prudence and business acumen, Treacy also acceded to the requests of the hierarchy to open schools in many parts of Australia.