Waldo H. Dubberstein, the former Defense Intelligence Agency analyst who apparently committed suicide Friday, said in a note left to his defense lawyers, "I am not guilty" of federal charges that he sold classified information to Libya through ex-CIA agent Edwin P. Wilson.

The note also said that after a long and meaningful career, Dubberstein did not feel he had the "capacity" to tackle a lengthy trial that would malign him, according to Howard Bushman, one of his lawyers.

Bushman also said Dubberstein indicated that people would not understand why he considered himself innocent of the allegations. Bushman declined to elaborate. The note was one of three pieces of paper found on or near the body of the 75-year-old Dubberstein, who was found dead Friday afternoon in a basement storage room in an Arlington apartment building.

Arlington police spokesman Tom Bell confirmed the accuracy of Bushman's summary of the note. Bell said the note apparently was written and dated April 24, five days before Dubberstein was found dead.

Bushman received a copy of the note yesterday from Arlington police, but said he and co-counsel Louis Koutoulakos had decided not to release the text of the message while police and the FBI are still investigating the death. Law enforcement officials have refused comment on the note.

Dubberstein, a career analyst and Middle East expert for the CIA and later the Defense Intellgence Agency, was indicted last Thursday by a federal grand jury in Alexandria on seven counts charging conspiracy, unauthorized release of classified information and bribery.

Dubberstein was scheduled for arraignment at 9 a.m. last Friday in U.S. District Court in Alexandria, but failed to appear. His body was discovered about 2 p.m. in a basement storage area at River Place, a Rosslyn apartment complex where he lived with a 32-year-old woman.

A law enforcement source said Dubberstein purchased a 12-gauge shotgun and ammunition at a gun store in Annandale three days before his death.

Bell said Dubberstein was found dressed in a black business suit. Police also found an envelope addressed to Bushman and Koutoulakos and a piece of paper with telephone numbers for the two lawyers, Dubberstein's wife, Marie, and Renate Strelau, the German-born woman with whom he was living, Bell said.

The papers have been sent to an FBI laboratory, according to Bell.

Bushman said yesterday that Dubberstein had first met Wilson when both were employed by the CIA. He said Dubberstein was approached later, in early 1977, by Wilson and asked to help in a "special mission" involving Libya. "Wilson said it was CIA," Bushman said.

"He Dubberstein relied on him when Ed came to him," Bushman asserted.

Bushman said Dubberstein had acknowledged to his lawyers that he traveled to Libya in 1978, but said he did so as an independent consultant, not as a Defense employe. Bushman said Dubberstein denied having furnished classified information to Wilson and the Libyans based on sensitive U.S. documents, as charged in the indictment.

The government alleged Dubberstein funneled data on Mideast troop strength and other military affairs both directly to the Libyans and, at times, through a Wilson employe, Douglas M. Schlachter. Schlachter has pleaded guilty to illegal dealings involving Wilson and the Libyans and is now in prison.