Grocery store prices in the Washington area rose 1.1 percent in June - a rate of increase twice the national average, according to Labor Department statistics published yesterday.

A separate government report showed that as area residents spent more of their income for food, they apparently spent less on some other kinds of merchandise at retail stores.

While retail sales in this area in May were up 7 percent from last year to $1.14 beillion, according to the Commerce Department, this figure was less then the 11.2 percent rate of inflation for the preceding 12 months. This indicates that retail purchases actually were down in real terms.

Soaring costs of fresh fruits and vegetables were the main factor in higher grocery store prices during June, according to the Labor Department. Retail prices of produce jumped 9.7 percent compared with a 2.8 percent rise the previous month here and a nationwide average gain of 3.1 percent in June.

Cereal and bakery product prices rose 0.5 percent last month while dairy products increased by the same amount. Prices of cola drinks, processed vegetables, poultry and bread also were up moderately, the government said.

About the only good news for Washington consumers came in the form of lower retail costs for beef, eggs and oils. The decline in beef prices was the first for any month this year.

The overall increase of 1.1 percent in grocery store prices in June was about the same as a 1.2 percent rise the previous month. Grocery prices here rose 1.2 percent in the first three months of the year and were about unchanged during April. For the first six months, however, food costs are up about 9 percent.

Area retailers yesterday attributed relatively weak sales during May to the gasoline shortage, during which many residents cut back on the number of trips to shopping centers. Sales at downtown Washington department stores during May, howeve, rose 13 percent from last year, one of the largest year-to-year advances for the major D.C. stores in the past decade.

William McDonald, vice president of Woodward & Lothrop, said business at his department stores had begun falling off "at the end of May and it continued through June and July . . . it's not dramatic but it is noticeable."

At the same time, he said. the "last couple weeks have been pleasant surprises and it could be because people are back in the market making up for their absence."

A spokesman for the Metropolitan Washington Board of Trade, who asked not to be identified, also said sales "have picked up more in the suburbs in the past week." He attributed the recent sales revival to warmer weather, an easing of gasoline shortages, and mid-summer promotional sales now in progress to reduce excess inventories.

Consumers interviewed yesterday cited a number of factors for cutting back on spending in recent weeks.

"I'm not doing as much buying as I normally do . . . my utility bill and rent both went up. So if it's not on sale, I don't buy it," said Jewelyn Sanders, a Washington resident, in front of the Woodies store downtown.

". . . With my credit cards, I was buying compulsively just to spend. The interest on my cards last year was $100 alone, so I left them at home," Sanders added.

At the Safeway store on 17th Street NW, Madelene Johnston of Northwest Washington said she borrowed funds to buy a freezer "because everyone said that meat prices would go up." Now she doesn't buy meat unless it's on sale, she added.

At the same time, Johnston said she buys vegetables and fruit at rural farm stands and grows her own alfalfa sprouts.

Spokesman for Safeway and Giant, the area's two major food chains, said yesterday that they have seen no major shifts in buying habits except that more people "than ever before" are using coupons and buying items on special sale.