Souris Regional High School, as an amalgamated entity, first took form in 1955.
The school was constructed beginning in the early fall of 1954, and was completed by spring of 1955. It is noted that the bulk of the building material for the school was provided by Matthew and MacLean Ltd., of Souris.
The graduation ceremonies of 1955 were held Friday, June 17 at St. Mary's Parish Hall. Over 500 people in total were in attendance. There were a total of 24 graduates that year, 13 girls and 11 boys. Guest speaker was Kier Clarke, Minister of Education.
Graduates were:
| Bushey, Peter |
| Clinton, Eleanor |
| Creamer, Sterling |
| Deagle, Winnifred |
| Dingwell, Violet |
| Dixon, Rita |
| Ellis, Reagh |
| Howlett, Urban |
| Hughes, Thomas |
| MacAulay, Gerard |
| MacAulay, Jean |
| MacAulay, Joanne |
| MacCormack, Helen Marie |
| MacCormack, Leonard |
| MacDonald, Helen |
| MacDonald, Paul |
| MacIntyre, Ruth |
| MacKinnon, James |
| MacPhee, Catherine |
| Mullalley, Desmond |
| O'Hanley, Jenny |
| Paquet, Joyce |
| White, Norma |
| Wood, Eric |