Roman Catholic High School was founded with funding provided by the estate of Thomas E. Cahill, a 19th-century Philadelphia merchant.

At 17, he opened a small store in Philadelphia, located between Pine and Spruce Streets on 26th at a wharf on the Schuylkill River.

Roman Catholic High School was dedicated on September 6, 1890, in a ceremony conducted by Archbishop Ryan of Philadelphia.

The significance of the historic landmark designation means the building on the corner of Broad and Vine Streets can never legally be torn down.

Beginning with the 2012–2013 school year, Roman announced the implementation of a 1:1 iPad initiative, starting with the incoming first-year students.

The article included the story of Joe,[8] a 59-year-old who spoke of his abuse at the hands of Father McGuigan, in 1966, when a ninth grader at Roman Catholic High School.

Coming from a poor immigrant family, Cahill sought to provide young men from similar backgrounds with the secondary education denied him.

The exterior is a three-story building of Victorian Gothic design, faced with "Lee, Massachusetts" marble (the same as selected for Philadelphia City Hall), placed on a granite base (quarried from Conshohocken, Pennsylvania) and sited to impact majestically at the intersection by prominent architect Edwin Forrest Durang.

The building originally had a 150-foot marble tower topped in copper at the corner of Board and Vine, destroyed by fire in 1959 and not replaced.

Initially, there were 20 classrooms, each designed to accommodate between 24 and 42 pupils, the building contained offices, a library suite, mechanical arts workshops, and on the third floor, a hall with a 700-person seating capacity, a gymnasium, and studios with natural lighting for drawing and modeling.

The Library and Information Center was renovated in the summer of 2013 upgrading computers, copiers, printers and furniture named in honor of John and Mary McShain.

[15] This new facility housed a sports training center, creative art studio, a multi-purpose room and the alumni association offices.

As part of "A Vision of Promise” on May 30, 2017, the school held a breaking ground ceremony on an additional new building with anticipated completion sometime in 2018.

The arts center is named for Barry and Elayne Howard, longtime supporters and benefactors of Roman Catholic.

This new expanded academic facility is located about a block away at 1212 Wood Street, and includes band rooms, instrument storage space, a computer-aided design lab, a digital photography studio, a piano lab, a small theater and an expansion for art programs.

This marks the team's second Red Division championship since the inception of the new Catholic League format, which began in 1999 and ended in 2007.

Boys Catholic High School is home to one of the most successful crews in North America, practicing for over ten months a year.

Recently it contributed a Lightweight Four to the Philadelphia Catholic League Rowing championships, finishing second in 2005 to Monsignor Bonner High School by six-tenths of a second.

In 2003 and 2005, two Roman students represented the United States at the Junior World Championships in Athens, Greece, & Brandenburg, Germany.

Mock Trial is a competitive club activity offered at the High School that is intended to simulate actual courtroom proceedings and allow students to assume the roles of attorneys and witnesses.

Roman Catholic students have a winning championship record and has won the state's Pennsylvania Mock Trial Competition.