Peoria Notre Dame High School is a Catholic parochial high school in Peoria, Illinois. It is the largest school in the Roman Catholic Diocese of Peoria with approximately 815 students. It has a college preparatory curriculum, and according to the school, most of the students graduating in recent years went on to college. The school uses an academy system with a trustee committee, oversight board, pastor's board, president, and principal.

Peoria is a city in and county seat of Peoria County, Illinois, United States. Located on the Illinois River, the city had a population of 113,150 as of the 2020 census. It is the principal city of the Peoria metropolitan area in Central Illinois, consisting of the counties of Fulton, Marshall, Peoria, Stark, Tazewell, and Woodford, which had a population of 402,391 in 2020.