Prince George's County and District of Columbia officials have agreed to cooperate in planning the future of the unused 216-acre Glenn Dale Hospital site near Bowie, County Council members were told yesterday.

For county planners, the tract, near state Rtes. 450 and 193, represents a potential site for a business-conference center, a high-tech research facility or an upscale residential development.

For the city, which won its battle with the federal government over the title to the property only last month, the sale of the site could prove lucrative, although no one is saying how much it could be worth on the private market.

The hospital, built in the 1930s for tuberculosis patients, later became a nursing home for the chronically ill and disabled, before being closed in January 1982. Twenty-six buildings still stand on the site.

In a letter sent to County Executive Parris N. Glendening, council members asked to be advised of any plans for the tract, which officials said is located in one of the fastest growing areas of the county.

Until Oct. 10, the General Services Administration and the Justice Department had sought to retain control of the Glenn Dale land and dispose of it as they wished. But the city argued successfully in U.S. District Court in Baltimore that it held title to the property.

Glendening, who felt that the county ought to have a say in the disposition of land within its borders, wrote D.C. Mayor Marion Barry on Nov. 2, requesting that Prince George's be included in the planning.

Glendening wrote that this would allow both jurisdictions to reach an "early, and mutually agreeable, development of the hospital tract."

Thomas Downs, D.C.'s city administrator, told a reporter that no decisions have been made, and that Glendening's offer had not been formally accepted.

But, he said, "We promised that we would not prejudge or predetermine any of those decisions until we talk to . . . " county officials.

Gordon Hubley, the senior marketing and development specialist at the county's Economic Development Corp., said prospective developers have already expressed interest in transforming the site, 1930s-era buildings and all, into anything from an educational institution to a business park.

The buildings' interiors, Hubley said, could be renovated, while maintaining the original facades, which he feels "add character."

"This is valuable property, and strategically located," said John Wesley White, Prince George's chief administrative officer, who also told the council that D.C. would cooperate with the county. "There would be a lot of benefits in putting it in the private sector."

Ideally, White said, the property could do both the city and the county some good if it is sold, providing D.C. with the money from the sale and the county with new taxes and possible employment benefits.

Robert Storey, the staff director of the D.C. Department of Administrative Services, said that a partial plan is already under way to handle the Glenn Dale situation.

"Our intent is to be as neighborly as we possibly can with Prince George's County," Storey said.