The publisher of a Washington weekly newspaper, attempting to move quickly after the announcement Thursday that Time Inc. would stop publishing The Washington Star on Aug. 7, said yesterday he plans to begin publication of a business newspaper five days a week, starting Sept. 8.

J. William Graff, publisher of The Business Review of Washington, a local 14,000-circulation business paper Graff acquired in 1978, told a news conference that the paper ultimatley could have a circulation of 50,000. The paper made its first profit during the 1981 first quarter.

"We think the need is there for good, cohesive, accurate business news," Graff said. "We've been doing that on a weekly basis. We intend to do that on a five-day basis now.

"We're already supplying the news; we're already generating it," Graff added. "We're just going to have more frequent deadlines. We're going to fill the market as the market supports the newspaper." 4tGraff said that although he earlier had considered expanding to a daily paper, the Star announcement pushed him to announcd his plans now. "The decision by the publishers of The Washington Star to cease publication has left a void in this area," he said in a prepared statement.

"This city without The Star also created a significant opportunity we intend to seize. We believe one of the shortcomings of The Star was its inability to identify a strong market and tailor itself to meet the needs of that market," he continued.

Graff said he is one of four stockholders in The Business Review. He would not disclose the other three owners and declined to discuss further details about the paper's financial status.

The paper was originally The Fairfax Business Monthly. Graff changed its name when he bought it and turned the paper into a weekly in September 1978. When The business Review becomes a daily paper, the day after Labor Day, Graff plans to change its name to The Washington Business Review.

Graff pledged to expand his publication's staff from 12 to 15 and said the paper would continue to be published at Comprint, a Gaithersburg printing company. He plans to move the paper from the Virginia suburbs to District offices.

The new paper will cost roughly the same as other dailies, Graff said. Until now, mot copies of the paper have been distributed free.