"Mom and Pop" corner grocery stores and small carryout shops in the District, ravaged by the 1968 riots and crippled by robberies, are enjoying a remarkable renaissance in the hands of a new group of immigrants - Koreans.

Koreans, many of whom barely speak English, now own an estimated 50 percent of these small grocery and carryout stores. They also are acquiring dry cleaners, cafeterias and gas stations, according to real estate brokers, food wholesalers and city business leaders.

The phenomenon, which is changing the face of one of urban America's most indigenous institutions, isn't limited to Washington. Koreans also are buying these small stores in Baltimore and Philadelphia, according to businessmen in those cities.

"Two or three years ago, you couldn't give away a corner store. But since the influx of Korean people, the prices are sky high," said Al Stern, a broker who has arranged many sales of these small stores in the Washington area.

The new immigrants are attracted to the stores for a variety of reasons. Like many other immigrant groups, the Koreans often have a serious language problem when they arrive here. And, like many other immigrant groups, they have found that often the only jobs they could get were for menial work.

"Owning your own business is much better than working at a menial job," said Eugene S. Kay, president of the 800-member Korean Businessmen's Association.

The Koreans quickly learned that they could buy and operate corner grocery stores regardless of their inability to speak or understand English well. Often they hire a local person to handle over-the-counter dealings, or make do with a combination of pointing and self-service by the customers. Wholesalers usually recommend the retail prices, and the new owners usually ask former owners for a couple weeks of one-the-job training.

"If you can count, you can stay in business," Kay said.

In addition, many of the stores can be purchase with relatively small amounts of cash - $10,000 to $15,000 down, plus $5,000 for inventory. Because of this, many Koreans can acquire their own business after living here only two or three years.

Underlying the business success of the Koreans is a tradition of hard work, a tightly organized system of family frugality and mutual help, and sometimes money smuggled out of Korea.

Kim Sun Ac, 43, and her husband, Kim Yong Bong, 47, bought a small carryout at 1737 7th St. NW three weeks ago. They typify the new Korean entrepreneurs.

Six years ago, Mrs. Kim was a housewife in Seoul who spoke no English. "I never worked hard in Korea," she said, interrupting her scouring of a grill. "In Korea women usually don't work. The men work, so I don't like here."

Five years ago she and her husband, a former Korean army officer, and their three children came to this country.

To earn enough money for the down payment on their first store, which they bought two years ago, "my husband worked two jobs and I worked two jobs. We worked every day. No days off seven days a week 16 hours a day," she said.

He worked as an auto mechanic during the day and a gas station attendant at night, while she worked two shifts in a restaurant.

And like other Korean immigrants they saved. "We don't go to the movies or anything, just save," she said.

Lee Chung Hee, 40, a former pharmacist, and her husband Lee Eung Sub, 44, a former engineer, who operate the Royal Farms market at 646 Rock Creek Church Rd. NW., did the same thing.

"I have bought one pair of shoes since coming to this country" six years ago, said Mrs. Lee, looking up from her cash register. "I have not been to the theater or to a movie. We don't buy new clothes. We just wear what we had from Korea."

The savings were then combined with money borrowed from relatives and funds brought from Korea.

One Korean, who worked as a government official and exporter-importer in Korea, said he smuggled $10,000 out of his country to start his grocery business here.

Many of the Korean immigrants had money in Korea because they generally are middle-aged, college-educated professionals such as school-teachers, pharmacists, lawyers and engineers. They are blocked from practicing their professions here by the language barrier, the primary deterrent to their completion of licensing requirements. Others are former U.S. or Korean army employes.

Until last year the Korean government allowed each immigrant to leave with $1,000. The limit was raised to $3,000 per person last year, according to Korean embassy spokesman.

Many of the immigrants said they came here to liberate their children from the pressure of a Korean education. But there has been a price: the parents' long hours working in their stores to earn money for the college educations they cherish for their children have strained the Korean tradition of family closeness.

In Korea, students must take examinations to get into junior high, high school and college. Many families hire tutors and send their children to night school to help ensure high test scores.

Admittance to a prestigious college leads to good positions in government, a Korean said, while failure on tests sometimes means suicide.

"It's too competitive, You can't imagine it in America," Mrs. Lee said.

Mrs. Kim said she seldom sees her children. She gets up every morning at 6 and fixes dinner for them. Then she and her husband leave for the carryout, stopping by various wholesale houses to pick up meats, bread and other foodstuffs. They will return to their three-bedroom Silver Spring apartment until midnight, three hours after the children have gone to bed.

With the changing ownership of the stores over a period of years, changes in the nature of Washington become apparent. Formerly, many of the stores' owners were Jewish immigrants. When they left, blacks took over. Now, although the neighborhoods remain primarily black, the Korean immigrant is becoming the dominant figure.

"People need these stores, and they have done without them since the [1968] riots, so any businessman is welcomed back," said Bill Jameson, director of a government-funded organization that lends assistance to minority businessmen.

Unlike the Jewish families they succeed, the Koreans don't live above their stores, but in apartments or homes in suburban Maryland and Virginia.

Traditionally, Jews, many of whom were Russian and Polish immigrants, operated the city's corner stores. But many of the stores were damaged in the riots 11 years ago and were closed. Other owners who remained came to fear the neighborhoods.

"We just wanted to get out of that area," said Rae Baron, who sold the Rock Creek Church Road store to the Lees and opened a delicatessen at 2643 Connecticut Ave. NW.

"It was dangerous. My husband had been held up a few times. You had watch how you walked out of the store. You had to wonder if these three guys were coming in with guns. It was too much pressure," she said, so after 18 years they left.

William Allen had been the head waiter at a downtown restaurant. After the 1968 riots he decided to open a grocery store on 7th Street because so many had been destroyed. He sold the store three years ago to Koreans.

"The price was good and I had a carryout up the street to depend on . . . I was 56 and you get tired of working seven days a week," he said.

He sold the carryout to the Kims three weeks ago.

Like other black owners, Allen said he had not intended to sell his business until a business broker visited him, asked if the store was for sale and made him a reasonable offer.

Since that first sale the store has been sold two more times, each time to another Korean. Several Koreans said that once a small store starts to prosper the first Korean owner will sell to another Korean and then will open a larger store.

Allen was more successful than many blacks who went into business after the riots. Many lost their stores, said the Chamber of Commerce's James Denson.

The black businessmen failed because, unlike the Koreans, the blacks had to borrow large sums of money from the Small Business Administration or from banks, Denson said. The loans usually took a long time to obtain and when granted they usually were below the requested amount, he said.

"If you go in [in business] with debt capital it will take you a number of years to erase that debt," said John Iglehart, deputy director of the Washington office of the Office of Minority Business Enterprise. "But if you go in with you own money or family money you don't have to pay out $1,000 a month to SBA or a bank . . . That's starting out rough when you have to borrow."

To combat any black resentment that might result from the growing Korean entrepreneurship, Kay, president of the businessmen's association, said he has suggested to his fellow countrymen that they hire blacks.

"I'm emphasizing to Korean people to hire people from the neighborhoods. You must be concerned about how the neighborhood feels," he said.

Following his own advice, Kay, a former press attache with the Korean Embassy, employs several blacks among the 25 employes at his large Coral Hill grocery.

Koreans began arriving in this country in large numbers after 1968, when changes in U.S. immigration laws increased the quota of Korean immigrants to the United States from 100 to 20,000 a year.

The U.S. Immigration and Naturalization Service estimates that 30,000 to 40,000 Koreans enter the country annually. The 10,000 to 20,000 additional Koreans over the annual quota are close relatives of naturalized Korean-Americans who are not covered by the limitation.

An estimated 25,000 to 40,000 Koreans now live in the Washington area.

"This country is very lenient and good to the immigrant," said Kay. "They can come in and buy what hey want." CAPTION: Picture 1, Lee Chung Hee waits on Henry Jones at the Royal Farms Market in Northeast. By Larry Morris - The Washington Post; Picture 2, Chang Su Kim, another of the new breed of corner grocers, sorts produce. By Margaret Thomas - The Washington Post