The Greater Washington Board of Trade claimed yesterday that it has helped bring 55 companies to the Washington area in the past four years, creating 1,000 new jobs and adding $9.4 million in personal income to the region's economic picture.

Its report on the "The Case for Washington," the board's business attraction program, said that 34 companies from around the country sent top executives to visit the metropolitan area in 1978 in conjunction with the Board of Trade's efforts, and of these 11 businesses came here or expanded their local activities.

The business group also plans to sponsor a second similar program in September, bringing about two dozen executives here to hear of the city's selling points, a board official said yesterday. "The Case for Washington" effort also has brought about another 80 currently active leads and prospects," the board said.

The program, a marketing effort run jointly with area economic development officials, stresses the area's economic condition, its accessibility and international flavor.

Among the success stories listed by the board were the moves of the National Restaurant Association, the Edison Electric Institute and Sambo's Restaurants here, along with the expansion of Pfaltsgraff Stores of York, Pa.

Although Board of Trade officials carefully pointed out that they were not solely responsible for the job switches, they do say their slide shows and literature were sent to the firms and associations in the early stages of their consideration of a move here.

Of the 55 "successes," 21 are associations and 34 are business and professional service firms. The trade groups represent 210,000 members and have a combined budget of more than $17 million, the board said.