“A lot of people come up to me and say, ‘Peel, I thought you were dead,’ ” said David Peel, who is not only alive but basically living the same life he led 40 years ago, when he was a muse for the Yippie and hippie movements in New York City.


At 68, Mr. Peel is past conventional rock ’n’ roll retirement age, but why retire if you can rock? He still has his acoustic guitar, his three chords and his festive, irreverent marijuana shout-music.


And lately he has found new relevance, and new listeners. He was a regular last fall at the Occupy Wall Street movement’s Zuccotti Park encampment, and now shows up in Union Square to jam with the Occupy protesters there.


“Not many of them know who I was, because it’s a new generation,” he said. But the old-timers like Kenny Vena, 72, certainly do. “Man, David Peel — you were an East Village icon,” he said upon spotting Mr. Peel strumming in the park one recent weekday. “ ‘The Marijuana Song,’ right?”


Mr. Peel smiled and broke into “I Like Marijuana,” one of the classics by his band, David Peel & the Lower East Side. With his songs about smoking pot and blasting the establishment, he became a fixture at counterculture marches and demonstrations beginning in the late 1960s.


Now he has written songs for the Occupy movement, including “Up Against the Wall Street” and “Mic Check, No Check.”


“If you want to win the movement, you must have music, the way John Lennon gave us ‘Give Peace a Chance’ for the hippie movement,” he said as the drum circle banged away.


Whoops — we had almost gone too far without letting Mr. Peel invoke his friendship with John Lennon. His business card bears a picture of him with Lennon and Yoko Ono, and he still wears his Lennon-style sunglasses. He became so associated with Lennon that in the early 1970s, the Federal Bureau of Investigation mistakenly put Mr. Peel’s head shot on an intelligence advisory about Mr. Lennon.


Mr. Peel was born David Rosario and grew up in Midwood, Brooklyn. He served in the Army in the mid-1960s and then began living downtown and playing the guitar in parks and on the street.


Lennon first saw Mr. Peel playing in Washington Square Park in 1971 and was introduced to him by the founders of the Yippie movement, Jerry Rubin and Abbie Hoffman. They all immediately began singing along to Mr. Peel’s song “The Pope Smokes Dope,” until the scene was broken up by the police.


Lennon began performing with Mr. Peel and signed him to Apple Records for the album “The Pope Smokes Dope,” which Mr. Peel said was widely banned, largely for its title.


At the time, Lennon was quoted as saying that Mr. Peel “writes beautiful songs” and that if he ever wanted to write non-controversial music, he could write hits as “easy as pie.”


He acknowledged the criticism that Mr. Peel “can’t sing, or he can’t really play,” and called Mr. Peel’s music simple, but added, “Picasso spent 40 years trying to get as simple as that.”


Mr. Peel has been high on that endorsement to this day. Regarding his three-chord approach, he said: “Technique is not talent. A jazz musician with a million chords can go all over the place and end up no place.”


Mr. Peel is unmarried with no children and lives in a rent-stabilized apartment on Avenue B. He survives on modest royalties, small gig fees and the sale of old and current records.


At Union Square, dressed in East Village black, with his long black hair pulled back in a ponytail, he made the rounds greeting the other old hippies — including Aron Kay, 62, the Yippie Pieman — and then began playing one of his classics: “I’m Proud to Be a New York City Hippie.”


Then he was walking along St. Marks Place. He wore his Lennon sunglasses and handed out fliers for an upcoming marijuana rally. When asked about his pot intake these days, he flashed a grin and offered a typically ambiguous Peel-ism: “Lose dope, lose hope.”


He said he planned to continue to sing on the streets and in the parks downtown “until the day I drop dead and go to rock ’n’ roll heaven.”