The Reagan administration, in a budget-cutting move, has decided to retire the 52 aging Titan II intercontinental ballistic missiles between 1983 and 1987, at least five years earlier than had been planned, according to Pentagon sources.

The Titan IIs, first deployed in 1963, are the oldest and largest missiles in the U.S. strategic arsenal. Each carries a single nine-megaton nuclear warhead with explosive power roughly 750 times that of the Hiroshima bomb.

The Titans are liquid-fueled, and thus far more dangerous to operate than other U.S. missiles.

Over the last few years, the Titans have been plagued by leaks of highly toxic fuels and two major accidents. Nonetheless, the Strategic Air Command has fought to keep them in service because their large warheads could wipe out enormous targets that otherwise would have to be covered by many other missile systems.

When a Titan II exploded in Damascus, Ark., last year, killing one airman and injuring 21, the Carter administration said the Titans would be used at least into the 1990s, when the giant, new MX intercontinental ballistic missile system was expected to become fully operational.

Pentagon sources said yesterday that the Air Force will make safety changes in the Titans as recommended earlier this year by an Air Force board that investigated the Arkansas accident. Those changes could cost from $20 million to $50 million, sources said.

A possible reason for the speed-up in retiring the Titan system was the retirement last July of Gen. Richard H. Ellis as commander of the Strategic Air Command and his replacement by Gen. Bennie L. Davis, chairman of the Air Force investigative board.

The Air Force is completing a $15 million cleanup of a Titan II site near Rock, Kan., where a major oxidizer leak in 1978 killed two airmen and destroyed the underground site. There had been plans to put the last remaining Titan II missile in that site.

Defense Secretary Caspar W. Weinberger told a House Budget Committee meeting yesterday that proposed budget cuts such as acceleration of the Titan retirement are "the best way to help achieve the administration's overall objectives of reducing deficits."

In 1967, a spokesman for then-defense secretary Robert S. McNamara told reporters that the Titan IIs would be retired beginning in 1971 because they were too dangerous to operate and too costly to maintain. Their replacements were to be the smaller, solid-fueled Minuteman missiles.

When the Nixon administration took office in 1969, the Titan retirement was delayed in hopes that the missile could be traded off in strategic arms limitation talks with the Soviet Union.

In fact, a deal was struck in 1972 as part of the SALT I treaty. Both nations agreed not to replace land-based missiles deployed before 1964 with more modern ICBMs. But they also agreed, in a published protocol, that such missiles could be traded for submarine-launched missiles.

In a private letter, however, President Nixon told Soviet Premier Leonid I. Brezhnev that the United States would not exercise its right to trade the Titans. The only choices were to maintain the Titans or take them down while the Soviets exchanged their similar missiles for new ones placed at sea.

In 1973, the Air Force began a program to keep the 54 Titan IIs going, although few spare parts were available. Test firing for the missiles was halted because there were no extra airframes.

Since the Kansas accident, criticism of the Titan system has grown, particularly among members of Congress from Arkansas, Kansas and Arizona, sites of the missiles.

One Air Force study, supplied to Rep. Dan Glickman (D-Kan.) in 1980, reported for the first time that hundreds of minor leaks had taken place at Titan II sites in the previous five years, and that dozens of airmen had been injured inhaling the deadly fumes.

When the most recent Air Force inquiry into the Titan system recommended hundreds of changes, including replacement of fuel detectors that worked only half of the time, members of Congress began questioning the administration on why the system was not being retired. That led to Weinberger's response yesterday.