An obituary in Thursday's editions of The Washington Post about Ralph Waldo (Petey) Greene, 53, gave an incorrect date of his death. Mr. Greene died Tuesday, Jan. 10, at Doctors' Hospital of Prince George's County.

Ralph Waldo (Petey) Greene, 53, former drug addict, armed robber, convict, media personality, winner of two Emmy awards, onetime guest at the White House and commentator on local affairs who could raise unpleasant and everyday issues with uncommon wit and candor, died of cancer yesterday at Doctors' Hospital of Prince George's County.

He was the community liaison of the United Planning Organization and the star of WOL radio's "Rapping With Petey Greene" and WDCA Channel 20's "Petey Greene's Washington."

These jobs provided him with a forum. But the substance of his work came from what he called his "PhD in poverty," an unblinking and encyclopedic knowledge of street life, and an ability to address people from all walks of life.

On radio and television, he talked about prison reform, drug addiction and alcoholism, teen-age pregnancy, welfare programs, education, politicians and business leaders, preachers, automobiles, clothes, presidents, the Redskins, and such street-corner pastimes as a game known as "callin' the dozens," in which two people try to out-insult each other for the benefit of onlookers.

But his favorite topics, on and off the air, were himself and the lessons he thought his life held for others.

"I had an eighth-grade education," he told The Washington Post in 1977. "I could possibly have made valedictorian. I could have said, 'Good afternoon, Mrs. Plummer and members of the faculty . . . . ' But my grandmother taught me a lot about people. Now I'm very well disliked by your local politicians. As soon as you get behind that desk and you put on that . . . three-piece suit you forget where you come from. Hustlers, pimps, prostitutes, they're still my friends."

He often talked of the material possessions that had come with his celebrity, emphasizing--particularly for his younger listeners in Washington's low-income black neighborhoods--that the rewards had come from legitimate work, not the criminal activity of his youth.

"I got my rings with my name on them and I got my Cadillac . . . ," he said in 1977. "I got a Cadillac because I want them to understand you don't have to be no dope dealer to have a car and because it's a big fun car and you can drive comfortably and people look up to Cadillacs."

He was an organizer as well as a talker. He was a principal founder of EFEC (Efforts for Ex-Convicts), a group devoted to helping prisoners return to what he called "the real world;" Bonabond, which was set up so that ex-offenders could help accused persons gain release on bail, and VOTE (Voice of the Ex-Offenders), whose members teach about voting in poorer neighborhoods.

Despite his frequent criticism of politicians, his death drew a tribute from Mayor Marion Barry:

" . . . Over the years Petey has made tremendous contributions to our community as a meaningful role model for our youth and the community at large. Petey Greene reached out to many segments of the community and he was a broadcasting pioneer in giving a voice to the poor and the needy and giving community residents a chance to make their voices heard . . . . He cared for the people. He spoke for the people and he gave people an opportunity to communicate with each other."

Petey Greene was born in the neighborhood of 23rd and L streets NW. He enlisted in the Army about 1947, served in Korea during the conflict and was discharged in 1953 for drug abuse. For the next several years, by his own account, he did odd jobs, played cards and drank.

In 1960, he committed an armed robbery at a small grocery store. In a moment of confusion, he used to recall, he fled into the freezer locker and found that he couldn't open the door. That's where the police found him.

Sentenced to Lorton Reformatory for 10 years, he became the facility's disc jockey. He also studied ways of getting out. A story he liked to tell was how he persuaded a fellow inmate to climb to the top of the 300-foot water tower and threaten suicide. The idea was that when all else failed Petey would come forward and persuade the man to come down. Nineteen minutes to talk the man down and six months to talk the man into going up in the first place, he said.

Shortly thereafter, he was paroled. With the aid of the publicity surrounding his feat, he soon was hired by UPO. He began his television career in the 1960s on WETA Channel 26. He joined Channel 20 a few years later.

A central aspect of his outlook was his sense of being an American and his belief that this country offers opportunities for all its citizens, including the disadvantaged.

"The most important thing is, I'm concerned about the plight of my people, and I don't come from Africa, and I ain't gonna drive no Cadillac back over there in no jungles," he said in 1979.

Greene, who lived in Oxon Hill, is survived by three children, Ralph Waldo III and Petra Greene, both of Miami, and Renee Freeman of Newark, Del., and a brother, Clayton Greene of Yonkers, N.Y.