Two of Prince George's County's most politically influential law firms will merge on March 1, combining legal staffs and a client list that includes major developers, government agencies and business groups.

Meyers & Billingsley, which has done business in the county since 1975, will join forces with Shipley & Curry, a Landover firm that has existed under various names for 26 years, partners in both firms confirmed yesterday.

Lance W. Billingsley, 44, a former chairman of the local Democratic Party, said the two companies reached agreement to merge over a breakfast meeting last weekend after negotiating for more than three months.

The new firm, to be known as Meyers, Billingsley, Shipley, Curry, Rodbell & Rosenbaum, will include partners whose combined government and private work will make the firm a $2 million-a-year business, Billingsley said.

Billingsley's firm does legal work for the county Private Industry Council, the city of Hyattsville, several hotel companies and the county housing authority. Most recently, he was awarded a contract for bond counsel work with the Washington Suburban and Sanitary Commission. He is close to County Executive Parris Glendening.

Russell Shipley, 50, who served as a deputy county attorney from 1960 to 1963, was previously a partner of Peter F. O'Malley, a county political power broker closely allied with Rep. Steny Hoyer (D-Md.).

"I really don't have any political clout ," said Shipley, who represented the developers of Brookefield, a proposed 2,500-acre "new town" that was rejected by the County Council last summer. "Thank God for Wayne."

Wayne Curry, 33, Shipley's partner, is a politically ambitious attorney active in the Jesse Jackson-inspired Maryland Rainbow Coalition. His name has been mentioned frequently in connection with 1986 countywide races. He has also been the high-profile counsel for Prince George's General Hospital. Curry said that his partnership with Shipley and his new alliance with Meyers & Billingsley will make for a more socially conscious legal community in Prince George's.

Lawyers, Curry said, "owe a certain amount of social consciousness and sensitivity to the areas in which they do business."

The two firms will consolidate their 12 lawyers in the Riverdale offices of Meyers & Billingsley, and eventually add four to six lawyers, Curry said.

Part of the reason business is booming for county law firms, lawyers said, is Glendening's year-old policy that encourages county agencies to do business with local county law firms. "It's like an affirmative-action program for lawyers ," Billingsley said.

But doing business with government has become so complex, Shipley said, that it is to a law firm's benefit to broaden its expertise in administrative law as much as possible. "The federal government is simple," he said. "It's Upper Marlboro [the county seat] where it's complicated."