The Soviet government yesterday told five more prominent Soviet Jews they are free to leave the country, bringing to 15 the number of refusenik cases resolved this week just days before Secretary George P. Shultz is scheduled to meet Soviet Foreign Minister Eduard Shevardnadze in Washington.

While western diplomats, Jewish leaders, refuseniks and emigres expressed happiness over the surprise announcements, they described the moves primarily as diplomatic gestures rather than a change in policy. On Monday 10 refuseniks, including the well-known activist and teacher Josef Begun, were given permission to emigrate.

"It's a miracle, like snow in summer," said Raya Katz of Brooklyn. Her brother Boris Kun, a 40-year-old radio engineer in Moscow, is one of the five to receive visas. "I haven't seen Boris in 15 years. I spoke to our mother in Israel and she still doesn't believe it."

Besides Kun, others given permission to leave yesterday were Boris and Emma Lanzman and Valery Lerner, all of Moscow, and Yevgenia Palanker of Yerevan, Armenia. Vladimir Slepak, who has himself been waiting for an exit visa for 17 years, told The Associated Press in Moscow that the five people were contacted by the Soviet Visa Office.

Pamela Braun Cohen, president of the Union of Councils for Soviet Jews, said, "I have a mixed reaction to all this. I spoke to Moscow three times today and their reactions are mixed, too. On one hand they feel that each release can be a precedent for another, but Inna Begun, Josef's wife, told me, 'Don't be too optimistic. We see this as a one-time shot.'

"The Soviets use Jews for barter every time there's a summit to ease international tension and to show they're humane," she said.

"Do not pay much attention to my case," Josef Begun, 54, told Reuter news agency in Moscow. "The problems remain." Natan (formerly Anatoly) Shcharansky, who spent more than eight years in Soviet prison until his release and emigration to Israel 18 months ago, said in Baltimore Monday night that the releases were tied to the Shultz-Shevardnadze meetings, which begin Sept. 15.

All of the families given visas have been waiting at least a decade, according to Cohen. The Lanzmans, seeking medical aid for their son who had leukemia, applied for emigration in 1980. They were refused and their son died that year. Emma Lanzman's sister Bela Belostrosky, who lives in New Jersey, said, "Everyone was taken completely by surprise. It took so long but we're overjoyed. Maybe this means more good things."

In July, Palanker's husband and two children received permission to leave but she was refused. Palanker, who works as a cyberneticist, was told she had scientific secrets.

Soviet officials have allowed 4,700 Jews to emigrate this year, according to Israeli figures. In recent years only about 1,000 Jews have been able to emigrate annually, but in 1979 about 51,000 were permitted to leave the country.

Cohen said the releases could "overshadow a rise in anti-Semitism." She pointed to an article printed in Monday's editions of the newspaper Vechernaya Moskva which said that city officials refused to allow a group of Jewish acitivists to hold a public discussion on what they say is growing anti-Semitism in the Soviet Union.

The paper had printed a letter from the activists to city officials requesting the meeting. Two of the signers, Viktor Brailovsky and Lev Osishchev, were among those granted visas Monday.

The seven who signed the letter -- including Viktor Brailovsky and Lev Osishchev, two of the refuseniks granted visas Monday -- were especially concerned with the rise of the group, Pamyat (Memory), which blames Jews and other minorities for threatening Russian culture.