Warren's Mill is a historic grist mill located near Millsboro, Sussex County, Delaware. The mill was built in 1910–18, and is a large two-story, large, rectangular, frame structure sheathed in clapboard and with a gambrel roof. It sits on a poured concrete foundation and has a concrete spillway. Also on the property is a contributing shed frame, with clapboard siding and a shingled gable roof.

It was added to the National Register of Historic Places in 1978.