Dominican High School was a Catholic, all-girls high school located in Galveston, Texas. Founded in 1882 by the Dominican Sisters of Galveston (who later became the Dominican Sisters of Houston), it was originally known as St. Mary's Dominican Academy. The school provided secondary education for young women, emphasizing both academic rigor and spiritual development in the Catholic tradition.
For much of its existence, Dominican High School was a prominent educational institution in Galveston, serving the local Catholic community and beyond. In 1968, facing changing demographics and educational needs, Dominican High School merged with Kirwin High School, an all-boys Catholic high school also in Galveston. The merger resulted in the formation of Galveston Catholic High School, which later became known as O'Connell College Preparatory School. Thus, Dominican High School ceased to operate as a separate entity, contributing its legacy and student body to the new co-educational institution.