Saint Aloysius on the Ohio (locally known as St. Al's) is a Roman Catholic parish in the Sayler Park neighborhood of Cincinnati, Ohio, United States.

The parish started in 1868 when German American Catholics who worshiped at Our Lady of Victory Parish in Delhi Township built a one-room schoolhouse for Lower Delhi children.

[2][3] In 1905, the original one-room schoolhouse was torn down, and the current school building opened on June 3, 1906.

In 2006, the Cincinnati/Northern Kentucky International Airport across the river paid for soundproof windows and air conditioning in the school building as part of a noise abatement program and also dropped the ceilings by 5 feet (1.5 m).

On December 23, 2014, the church, school, and rectory – four buildings in all – were added to the National Register of Historic Places, owing to their locally significant architecture.