Maryland Route 330 (MD 330) is a state highway in the U.S. state of Maryland. Known as Massey Delaware Line Road, the state highway runs 3.72 miles (5.99 km) from MD 313 and MD 299 in Massey east to the Delaware state line in eastern Kent County, where the highway continues east as Clayton Delaney Road. MD 330 was constructed in the mid-1950s but was not designated MD 330 until the late 1980s.

MD 330 begins at a four-way intersection with MD 313 and MD 299 in Massey. MD 313 northbound heads west as Galena Massey Road and southbound as Millington Massey Road. MD 299 heads north as Massey Road toward Sassafras. MD 330 heads east, crossing the Centreville Branch of the Northern Line of the Maryland and Delaware Railroad just south of the junction of the Centreville and Chestertown branches of the Northern Line. The state highway passes through a mix of farmland and forest, passing the Massey Aerodrome and along the edge of the Millington Wildlife Management Area. MD 330 reaches its eastern terminus at the Delaware state line, where the road continues east as Clayton Delaney Road in the southwest corner of New Castle County.

The highway from Massey east to the Delaware state line was constructed as a modern road starting in 1954. However, the road remained a county highway until it was designated MD 330 around 1989.

The entire route is in Kent County.