MOSCOW -- Soviet rock music, one of the first areas to thrive under Soviet leader Mikhail Gorbachev's new policy of glasnost, or openness, is now being reined in by a campaign orchestrated by Yegor Ligachev, the Kremlin's leading conservative voice.

Earlier this month, Ligachev presided over a meeting on youth culture held at the Communist Party Central Committee, at which it was decided that permissiveness in music had gone too far, according to well-informed sources.

"They came to the conclusion that they had given youth too much, that rock should be controlled," said one source. In addition to Ligachev, the party's top ideologue, the meeting was attended by Culture Minister Vasili Zacharov; Alexander Aksyonov, head of state television and radio, and other officials, sources said.

It is still unclear how far the clampdown on rock music will go, but several people involved in music and the news media see it as a test of Ligachev's clout in cultural affairs. Since last spring, the 66-year-old Siberian, who ranks second in the Kremlin, has diverged sharply from Gorbachev on issues of culture and history, warning explicitly against the infiltration of "mass bourgeois culture."

Rock music -- loud, brash and imported from the West -- is viewed by many here as antithetical to Soviet values. In the past year, the thumping beat and outrageous outfits of young metallisti -- as heavy metal music fans are known -- have upset members of the older generation, providing the basis for a backlash.

Although his policy of relaxed controls opened the way for the rock revival here, Gorbachev, in a book published this month, reminded readers of harmful effects of certain kinds of cultural imports "alien to us, which bred vulgarity and low tastes and brought about increased ideological barrenness."

According to sources, a Central Committee resolution with guidelines on rock music is being prepared, although probably only for internal distribution. The measure is not expected to ban rock music, which has already achieved limited official recognition, but to curb its free-wheeling development, particularly among teen-agers, the sources said.

Already state-run television and radio are limiting rock programs, excising more daring and experimental groups and sticking to middle-of-the-road styles. Several people connected with the music world said some station managers, anticipating a crackdown, already have pulled western music videos off the air.

Outspoken lyrics and theatrical behavior on stage also are being quietly censored and, according to reports circulating in the music world, some groups may be banned from official or semiofficial performances.

"It is a big political mistake," said one cultural official who asked not to be named. "It is always hard to take away something you have already allowed."

Not all rock musicians are alarmed, however. Some note that the strides made over the past two years are already too great to turn the clock back.

"You have to remember everybody was against rock music a few years ago," said one musician. "Now it is only the minority. There will always be people who don't like it."

This summer was probably the high point of rock's emergence from underground. Television showed Michael Jackson, once anathema here, and large public concerts were staged for groups whose muscial styles range from punk to new wave to heavy metal.

But those who object to rock music have since made themselves heard. Protests from parents and pensioners run deep, touching antiwestern and anticapitalist feelings that are at the root of the conservative reaction in the Soviet Union on other fronts as well.

Last August, Ligachev reportedly circulated an initial letter complaining about excesses in rock music.

On Nov. 9, the Communist Party newspaper Pravda published a letter attacking rock music. The letter, signed by well-known writers Valentin Rasputin, Yuri Bondarev and Vaili Belov, called rock "mentally and morally damaging" and said its harmful effects have been proven by scientists and doctors around the world.

Quoting a deceased composer unknown to the Soviet union of composers, the three writers said, "Live rock has become the scourge and poison of our lives," affecting "every new stream of youngsters."

The reaction against rock music comes just as rock is making its way into the official music world here. The union of composers last week sponsored its first rock concert, and next month the Moscow Komsomol, or Young Communist League, is sponsoring a rock festival. The festival is expected to take place, but the list of performers is still being decided.

Some predict that attempts to suppress the growth of rock will backfire, since cultural organizations, under new "self-financing" rules, will be forced to stage concerts that draw crowds so they can make ends meet.

"Rock will be there. It will just be in different clothes," said one concert organizer.