An unabashed geek, Pee-wee Herman wore tight gray polyester suits with skinny bow ties and white shoes. He spoke frenetically with a nasally voice. To the dismay of many parents, his catchphrases — especially “I know you are but what am I?” — became popular adages of the adolescent set.

Pee-wee’s neighborhood was a curious one, inhabited by Chairry, a talking chair; Pterri, a blue pterodactyl; and an ant farm that communicated by forming words. Miss Yvonne, “The Most Beautiful Woman in Puppetland,” in Pee-wee’s view, frequently stopped by wearing prom-like gowns.

Critics called Mr. Reubens’s alter-ego petulant and sweet, and they marveled at his stardom, which by the end of his career had outlasted the actor’s arrests on indecency and obscenity charges.

“It could be said that he appeals to young audiences because he represents the confusions of a boy who refuses to grow up — that he’s a Peter Pan of the shopping-mall era,” New Yorker film critic Pauline Kael wrote in a 1985 review of the movie “Pee-wee’s Big Adventure.” “But there’s another element in the character: like a lot of teen-age consumers, he’s hooked on American kitsch.”

Experts on adolescence said his appeal was obvious.

“Paul Reubens is a clown, in a long tradition of clowns who act like babies,” Ava Siegler, the director of the Child, Adolescent, and Family Clinic of the Postgraduate Center for Mental Health in New York, told Rolling Stone in 1987. “Pee-wee allies himself on the child’s side, against the grown-up world. Boundaries — between reality and make-believe, past and present, child and adult — are subverted, released or obliterated.”

Mr. Reubens developed the Pee-wee character in the late 1970s while performing with the Groundlings, a Los Angeles improv group. “I used to have a little harmonica, a little teeny one about one inch long, and it said PEE-WEE on it, and the name stuck,” he told Rolling Stone.

In 1981, Mr. Reubens starred in “The Pee-wee Herman Show,” a not exactly PG satire of children’s television that sold out nightly at Los Angeles’s Roxy nightclub. The show later became an HBO special and is considered a cult hit.

Mr. Reubens, as Pee-wee, became a frequent guest on “Late Night With David Letterman” and other talk shows. With his popularity skyrocketing, CBS producer Judy Price tried to persuade him to do a live-action children’s show — a novelty given that animated shows were cheaper to produce and more likely to succeed.

“It was the classic Hollywood story,” Mr. Reubens told United Press International. “It got so that every time I came home there was another Judy Price message on my answering machine.”

He finally agreed, and “Pee-wee’s Playhouse” debuted in 1986. The movie “Big Top Pee-wee” followed in 1988.

Mr. Reubens’s reputation was damaged when he was arrested in 1991 at an adult movie theater in Sarasota, Fla., and charged with indecent exposure. Detectives did not know they had arrested the actor who portrayed Pee-wee Herman, the Associated Press reported, until Mr. Reubens volunteered his identity.

“Pee-wee’s Playhouse” had already been canceled, and CBS quickly dropped the remaining reruns from its Saturday-morning children’s television programming.

Mr. Reubens pleaded no contest and agreed in a deal with prosecutors to co-write and co-produce an anti-drug public service commercial.

Mr. Reubens again attracted scrutiny in 2001 when Los Angeles police conducted a search of his erotica collection. In 2004, he pleaded guilty to a misdemeanor charge of possession of obscene material. Prosecutors dismissed a more serious charge of child pornography.

After his 1991 arrest, Mr. Reubens maintained his acting career but took a years-long hiatus from Pee-wee Herman. He appeared in movies including “Batman Returns” and “Buffy the Vampire Slayer” (both 1992) and “Matilda” (1996), among many others. For “The Nightmare Before Christmas” (1993), he collaborated with filmmaker Tim Burton. They also worked together on “Pee-wee’s Big Adventure.”

On television, Mr. Reubens acted on shows including “Murphy Brown,” “Everybody Loves Raymond,” “Ally McBeal,” “Rugrats” and “30 Rock.” He also played criminals on NBC’s “The Blacklist” and in the film “Blow” (2001) about a cocaine kingpin.

Mr. Reubens eventually revived Pee-wee Herman, including for a Broadway production of “The Pee-wee Herman Show” in 2010 and the 2016 movie “Pee-wee’s Big Holiday.”

“I wrecked it to some degree, you know?” he told the New York Times in 2010 of his signature character. “It got made into something different. The shine got taken off it.”

But “at a certain point I just wanted to have a better ending to my career,” he also said. “More than anything, I felt like I love Pee-wee Herman, and I love what it was and what it is, and what it can still be.”

Paul Rubenfeld was born Aug. 27, 1952, in Peekskill, N.Y. His father, an American military pilot during World War II and later a founding member of the Israeli air force, ran a car dealership in New York. The family moved to Sarasota, where Mr. Reubens’s parents ran a lamp store. His mother was an elementary-school teacher.

A jokester from an early age, Mr. Reubens began acting at his elementary school. Years later, he remembered that his imagination was fired by the many circus actors who spent the winters in Florida.

He told a reporter — perhaps in jest, perhaps not — that if his acting career ever fell through, he would join a circus.

Mr. Reubens studied at the California Institute of the Arts and acted on the Los Angeles theater scene before joining the Groundlings, working as a busboy and selling Fuller brushes to support himself. After his early success as Pee-wee, he auditioned for “Saturday Night Live” but was not invited to join the cast. He soon found major success with “Pee-wee’s Big Adventure.”

Survivors include a sister and a brother.

Critics and psychologists were never short on theories about why Pee-wee became so popular, but Mr. Reubens never thought about it much.

“I don’t like to get too intellectual about it, you know, about what’s funny,” he told The Washington Post in 1985. “To me, something’s either funny or it’s not funny. I don’t like stuff that’s funny because it’s making fun of somebody or you have to know some particular thing for it to be funny, or you have to have some particular background. I like just funny.”