Scoil Mhuire competes in Monaghan County Athletics Board competitions. There is a strong tradition of athletics in the school. Saint Mary's currently hold both the Large School Boys' Cross Country and Track Titles and have retained both titles for a record number of years.
The cross country race takes place in March or April. In recent years the event has been held at the Scotstown GAA grounds in Kilmore, Carrickmacross and at Beech Hill College.
Beech Hill College is usually the venue for track events in June. The Carrick Aces Club hosted the event in 2012.