Two stockholders of Financial General Bankshares Inc. yesterday filed a class action lawsuit against the group of Middle Eastern investors who own about 20 percent of the Washington bankholding company.

The lawsuit, filed in U.S. District Court, also named as defendants some former Financial General shareholders who sold their stock to the Middle Eastern Group and Bert Lance, the former Director of the Office of Management and Budget, who helped the Middle Eastern group buy into the bank.

The lawsuit was filed by Philip I. Berman of Allentown, Pa., and the Philip and Muriel Berman Foundation on behalf of any Financial General stockholders who sold their shares between Dec. 1. 1977, and March 31, 1978.

The lawsuit charges that because the Middle Eastern group failed to disclose it was seeking control of the bank at that time, any investors who sold stock then did not get as much for their shares as they would have if the takeover attempt had been known.

A similar charge was raised by the Securities and Exchange Commission in a civil lawsuit filed two years ago against the same defendants.

In that case, the federal court ordered that anyone who sold stock to the Middle Eastern group -- without knowing the group's plans -- was entitled to at least $15 a share, the price the group paid to persons who knew they were trying to take over the company. The new lawsuit apparently is aimed at getting a similar benefit for persons who sold stock in the open market at the same time.