Expanding its Multinational Group into Eastern Europe, Riggs National Bank has named a new vice president to develop banking connections in Communist bloc countries.

Appointed to the new post was Edward T. Wilson, who as an executive of the U.S. Chamber of Commerce set up bilateral business liaison groups with five Eastern European countries.

Wilson said Eastern Europe -- principally Hungary, Romania, Poland, Yugoslavia, East Germany and Czechoslovakia -- will be the next major market to be tackled by Riggs' expanding international banking division.

International banking accounted for about 30 percent of Riggs' business last year, the bank's annual report shows. Foreign liabilities amounted to $684 million of the bank's $2.3 billion total liabilities, and internaional operations produced an estimated $4.1 million of Riggs $18.3 million profits.

Wilson said Riggs' decision to seek more business in Eastern Europe reflects not only the bank's increasing emphasis on overseas operations but also the growth of Washington as an international financial center.

Trade with Eastern Europe -- and banking business as well -- is expected to increase with the extension of most favored national status to more Communist-governed countries. Poland and Yugoslavia already qualify for favorable trade treatment, and East Germany and Czechoslovakia are seeking it.

Wilson said Riggs hopes to build business in those countries by developing its existing embassy accounts, establishing correspondent ties with East European banks, and providing trade and project financing.

The bank already is giving financing to a local importer of fine porcelain china from Hungary. Machinery, semimanufactured goods, clothing and foods -- principally canned hams from Poland -- are now Eastern European nations' major exports to the United States.

Commerce Department statistics for the second quarter of 1978 show that the U.S. imported goods worth $198 million and shipped exports valued at $350 million to Poland, Hungary, Czechoslovakia and Romania.

That group of nations has increased its borrowings from the U.S. recently and is seeking to increase exports to this country.