Oella is a mill town on the Patapsco River in western Baltimore County, Maryland, United States, located between Catonsville and Ellicott City.

Stock in the company was issued to fund a series of industrial mills, the largest working with cotton and wool.

Dickey and Sons, naming the mill "Oella" after the first woman to spin cotton in America.

The Oella Methodist Church is a simple frame building with a tower on the northeast corner, which has been converted into offices.

[1] Also listed on the National Register at Oella are the Ellicott's Mills Historic District and Mount Gilboa Chapel.