OCEAN CITY, MD. -- Maryland's state-operated commuter rail service plans to open four new stations between Baltimore and Washington in the next five years and replace two old ones, officials reported.

Richard Keen, head of the State Railroad Administration, said officials hope the new stations will help attract more riders to the system. It carries about 4,000 commuters daily on lines that run between Baltimore's Camden and Penn stations and Union Station in Washington.

The $14 million expansion program is contained in the state's Consolidated Transportation Plan for fiscal 1988 through fiscal 1993, released here by Stephen Zentz, deputy state secretary of transportation, at a meeting of the County Engineers Association of Maryland on Friday.

Officials said 80 percent of the work would be financed with a federal grant, with the state paying the rest.

The line that runs on CSX tracks from Camden Station to Washington will receive new stations at Relay, Annapolis Junction, South Laurel and Greenbelt. Along the Amtrak line from Baltimore's Penn Station, the Bowie station is being moved, while the Seabrook station is being rebuilt.

Keen said the Bowie station, located in an old downtown section of the city, is hemmed in with no room to expand, and the Seabrook station has parking for only 30 cars.

He said the new site near Bowie State College has room for parking.

A three-year-old railroad administration study showed that the service's CSX line between Baltimore and Washington had the lowest ridership of any of the system's three lines. Yet it has the greatest potential because of development along Rte. 1, which the tracks roughly parallel.

The Annapolis Junction station is to open next spring. The Greenbelt station, which is to tie in with the Washington Metro's Green Line, is to open in the spring of 1989, two years before Metro is scheduled to arrive.

The South Laurel and Relay stations are to open in the summer of 1990 and 1992, respectively.