The Soviet Union resumed broadcasting into Iran yesterday anti-American radio programs that the Carter administration fears could endanger American lives in the continuing social upheaval against Shah Mohammad Reza Pahlavi.

Critical Soviet broadcasts appeared to have ceased last Thursday after the administration publicly rebuked the Russians for making "false" and "unhelpful" statements about involvement by the Central Intelligence Agency in Iranian affairs.

The apparent resumption of propaganda attacks by Radio Moscow brought an immediate response from the administration. A senior U.S. embassy official, noting the brief respite, again labeled the broadcasts as "unhelpful" in a conversation with Soviet foreign ministry officials in Moscow yesterday, State Department officials said.

The previously scheduled discussion covered a broad range of American and Soviet attitudes on Iran, the official said. Another item brought up was the movement of U.S. naval vessels into the South China Sea last week at the time that the administration's concern over Russian intentions toward Iran appeared to be growing.

U.S. officials said that while there was no air of confrontation buliding over Iran, the administration wanted to make sure that the two superpowers understood each other's intentions clearly.

In a Persian-language broadcast yesterday, Radio Moscow asserted that "the dangers facing the Iranian people are coming" from the United States "and its policy." It drew attention "to the activity of the American CIA, which often sends uninvited guests to Iran," according to a text of the broadcast carried by a U.S. government monitoring service.

The French press agency also reported from Moscow that the Soviet radio had accused "the shah, a group of high-ranking Iranian officers, the U.S. State Department, the Pentagon and the CIA" of collaborating to crush dissent in Iran. The news agency quoted Radio Moscow as specifically attacking Shapur Baktiar, named by the shah as premier-designate, as an American political tool.

In a carefully considered policy decision, the administration took the unusual step last week of publicly denouncing Russian broadcasts and a Pravda article that claimed that 60 CIA operatives had been sent into Iran to foment trouble.

The protest was delivered in the form of a strong denial by State Department spokesman Hodding Carter last Thursday at his regular daily briefing. Its tone was reportedly reflected in private diplomatic communications the administration had with the Russians at about the same time.

Although spokesman Carter did not disclose it at the briefing, administration fears that the broadcasts could spur anti-American violence in Iran lay behind the public rebuke to the Russians, according to U.S. officials.

That danger was stressed in cables to the State Department last week by the U.S. ambassador in Tehran, William H. Sullivan. Sullivan's cables reportedly warned that specific attacks on Americans would follow if the Russian attacks continued.

At American oil company executive, Paul E. Grimm, was murdered in Iran by unknown assailants on Dec. 23 and death threats have been delivered to a large number of the estimated 35,000 Americans still in Iran.

In a decision approved by Washington but evidently initiated by Sullivan's recommendations, the embassy began on Sunday advising American dependents to leave Iran. U.S. officials say that only about 50 to 100 U.S. oil technicians are now left in the oil fields. Until last month there were nearly 1,000 Americans living around the fields, whcih were then producing 5 million to 6 million barrels of petroleum a day.

Administration specialists interpret the Russian broadcasts as evidence that Kremlin has concluded that the shah is now certain to fall. These policy analysts believe the Russians are now positioning themselves for good ties with the government that is likely to follow the shah, a process that the White House evidently fears will inevitably further weaken the shah.

Soviet aircraft evacuated about 700 Russian dependents from Iran in recent weeks as the protests against the shah turned more violent and he appointed a military government to deal with the widespread social unrest.

The administration's most open show of concern came last last week when it allowed reporters to know that the U.S. Navy aircraft carrier Constellation, accompanied by a cruiser, two destroyers and a frigate, had been ordered to alter course and move toward the approaches to the Indian Ocean.

A Pentagon spokesman said the carrier was engaged in "routine operations" in the South China Sea yesterday and that there were no current plans to move it closer to the Persian Gulf region. Other administration officials said President Carter was not now contemplating moving the carrier into Iranian waters.

Soviet foreign ministry officials challenged the American diplomat they met with yesterday in Moscow on western news accounts that the president was considering moving the naval task force into the Persian Gulf region as a show of force, according to a State Department official. These reports were labeled "false" by the U.S. diplomat.