St. Mary's Episcopal Church is a historic Episcopalian parish in the city of Hillsboro, Ohio, United States.

Constructed during the middle of the 19th century, this Gothic Revival church building has been named a historic site.

St. Mary's considers its history to have begun in 1851, when occasional Episcopalian services were conducted in the Highland County Courthouse.

[3] Built on a foundation of limestone and covered with an asphalt roof, the church has substantial components of wood and glass.

Lit by six ogive-arch windows, the interior features oaken pews installed at the time of construction, a lofty vaulted ceiling, and wainscoting made of marble.