The chairman of the Senate Intelligence Committee told the Justice Department yesterday that "a number of troubling questions remain" in the death of former CIA official John A. Paisley, whose body was found last October in Chesapeake Bay with a bullet in his head.

Committee Chairman Birch Bayh (D-Ind.), said in a letter to Attorney General Griffin Bell that the FBI should begin an immediate investigation into Paisley's death. Bayh ordered that the findings of the committee's own investigation be given to the Justice Department.

The senator said, however, that it would be "premature" to disclose any of the findings until the FBI has looked at the case. He said the information was given to Bell "because of the FBI's primary jurisdiction over counterintelligence matters within the United States."

Paisley disappeared Sept. 24 after setting sail alone in his 31-foot sloop, the Brilling. Although the boat was found aground the next day, Paisley's bloated body, weighed down by two diving belts, was not recovered until a week later.

Maryland police still classify the death of the former director of the CIA's Office of Strategic Research as "undetermined." Paisley's estranged wife Maryann, also a former CIA employe, has said she doubts that the body found in the bay was that of her husband. She has hired Bernard Fensterwald, a Washington attorney, to investigate her husband's disappearance.

Justice Department spokesman Terry Adamson said Bell has ordered the FBI to examine the Senate committee's findings and the bureau's own information on Paisley's death. An assessment will be made "reasonably promptly" of the need for a fullscale FBI investigation, Adamson said.

Sen. William V. Roth (R-Del.), who-first caled for an investigation into Paisley's death, said yesterday that "a could of suspicion" still surrounds the case.

"The Paisley affair was all set to be swept under the carpet; fortunately it didn't sweep too well," Roth said.

Roth said he is concerned by "inconsistencies" in the way the CIA has answered questions about Paisley's access to classified information, including his knowledge of a top secret manual on the KH11 reconnaissance satellite -- which can monitor foreign troop and equipment movements by photographing them from space.

"The CIA said at first that Paisley had no access to sensitive documents. Of course he did," Roth said. Roth also said it was "inconsistent" that the CIA should claim that a high-level official such as Paisley would have nothing to do with the KH11 satellite.

Roth said that if a "junior watch officer" such as William P. Kampiles, convicted last November of selling satellite secrets to the Russians, had access to the KH11 information, then Paisley also would have had access.

Roth and some other senators have asked publicly if there is a link between Paisley's death and the theft from CIA headquarters in Langley of 14 top secret manuals describing the satellite system. The theft was discovered last August.