The Cunard Line has canceled $35,000 in advertising in Sunday Times after the paper reported that U.S. health inspectors found cockroaches and other filth in galleys of QE2 and sister Cunard ships.

The offending story and another in the paper's companion daily, the Times, are expected to cost the two nearly $100.000 in Cunard ads this year.

This classic example of advertising pressure on the press is perculiarly ironic. Cunard's chairman, Victory Matthews, is also the chairman of the Beaverbrook newspapers, publishers of the mass circulation Daily Express.

When Mathews' conglomerate bought the Beaverbrook papers last summer, he said.

"If we are going to ask good people to write, we must allow them to write what they want . . . They must have the freedom to write what they want to write."

Through his secretary, Matthews asked the Washington Post, for 24 hours to frame a comment to reconcile the approval inconsistency between his words and deeds. After 24 hours had passed, he made no comment.

John C. Mitchell, managing director of Cunard's passenger ship division, told the daily Times:

"If we are going to consider where best to spend our advertising money, we are not going to choose a place where a hostile environment has already been created by editorial policy, This is perfectly straight normal commercial sense."

Michael Mander, deputy chief executive and marketing director for both Times newspapers and others in the chain, has kept a stiff upper lip over the affair.

"None of our advertising staff is crumbling," he said. "They do know what our papers are about and we can't accept a threat to change legitimate editorial matter."

A Cunard ad scheduled to run in the Sunday Times on Jan. 22 was canceled on two days' notice. Five others were also killed.

Last year, Cunard spent $58.000 in the Times group. Since the British economy has improved this year, an outlay of almost $100,000 could have been expected this year.

Cunard told the Times of its anger in a letter on Jan. 9 from Mitchell."We were extremely disturbed" over the Sunday Times article of Nov. 6, Mitchell wrote.

"Without making the point too obviously your group has benefited from the marketing efforts and skills which have been out into selling this project."

The story that caused the storm was based on the periodic reports made by U.S. Public Health Service inspectors who check ships in U.S. ports. Their findings were obtained by the Sunday Times through the U.S. Freedom of Information Act. British health inspectors also examine ships, but there is no freedom of information law in Britain.

According to the report in the Sunday Times, the American inspectors reported that on a typical voyage in 1976, Cunard's new Countess liner was mixing ice cubes for drinks with raw fish; carrying cubes in dirty drums and running a coliform count of fecal organisms in the ice that was too high to measure.

The report said the newer Princess had been cited for irregularities on all 13 U.S. health inspections through October 1977 and the QE2 reportedly had passed it latest test wiht flying colors, but a spring cruise reportedly had left 216 passengers with diarrhea.

What broke Cunard's bow, however, was a front page article in the daily Times on Jan. 6. It reported that QE2's Christmas Caribbean cruise had been disrupted by a breakdown in the distillers supplying water to the boilers.

But what really hurt was that the Sunday Times article about uncleanliness "was copled at irregular intervals in various American newspapers, and still goes on popping up all over America," where Cunard cruises draw many customers.

Sunday Times editor Harold Evans said he was "disturbed" by Mitchell's suggestion "that the advertising by Cunard should in some way give it a special position. I could not accept this."

Dally Times Editor William Rees-Mogg told Mitchell;

"I feel I must remind you that any attempt to introduce commercial considerations into complaints about the editorial conduct of a newspaper are bound to be resented and rightly resented, since they cut across the basic concept of the freedom of the press from commercial pressures."

Is it more difficult for papers here than in the United States to resist pressure from advertisers. The typical near monopoly position, but in Britain, eight papers compete daily and Sunday for advertisers's revenues.