MD 302 begins at an intersection with US 301 (Blue Star Memorial Highway) about midway between Church Hill and Barclay in Queen Anne's County.

MD 302 heads east as two-lane undivided Barclay Road, which crosses Red Lion Branch near its source west of Stevens Corners.

In the center of town, the highway has a grade crossing with the Centreville Branch of the Northern Line of the Maryland and Delaware Railroad just west of the route's junction with MD 313 (Goldsboro Road).

MD 302 crosses Unicorn Branch at its source, and the highway begins to follow the Queen Anne's–Caroline county line at its intersection with Woodyard Road.

East of the town, shortly after crossing Beaver Dam Ditch, MD 302 reaches its eastern terminus at the Delaware state line.