Heatherton is the daughter of the vaudevillian and television pioneer Ray Heatherton (1909-1997), affectionately remembered by New York area baby boomers as The Merry Mailman, the endearingly cheerful and reassuring host of a long-running (1950-1964) series of children's shows seen over local television. Joey began her career as a child actress, and between 1961 and 1963 was a semi-regular on The Perry Como Show, playing an exuberant teenager with a perpetual crush on the fiftyish "Mr. C". Another middle-aged crooner who was the object of her on-screen adoration was Dean Martin, who invited her to perform numerous times on his popular NBC Thursday night TV variety hour. From June to September of 1968, along with Frank Sinatra, Jr., she co-hosted Martin's summer substitute musical comedy show Dean Martin Presents the Golddiggers. She also made multiple appearances on the many other variety shows proliferating 60s television, such as The Andy Williams Show, The Hollywood Palace and The Ed Sullivan Show. Particularly memorable was her guest shot on a May 1969 Tonight Show, where she energetically coached Johnny Carson on the finer points of doing "The Frug". Vietnam veterans and that era's TV viewers fondly remember her as a long-time (1964-1976) member of Bob Hope's USO troupe, delighting the GIs with her enticing singing, dancing and provocatively revealing outfits. Excerpts from the USO tours were televised as part of Hope's long-running series of NBC monthly specials, culminatating in the high-rated Christmas shows, where Joey's segments were always highly appreciated.

Additionally, throughout the 1960s, she interspersed her variety show appearances with strong dramatic turns in three theatrical films and on numerous episodes of Route 66, Mr. Novak, Arrest and Trial, Breaking Point and other series. The films Twilight of Honor (1963), Where Love Has Gone (1964) and My Blood Runs Cold (1965), showed that she could hold her own with veteran actors such as Claude Rains, Bette Davis and Susan Hayward, but did not result in a sustainable film career. Each of the three films had her character involved in murder. In Honor, her film debut, she was the sluttish young wife of Oscar-nominee Nick Adams who is accused of murder precipitated by her infidelity. The only one of the three films to be made in color, 64's Love was a big-budget melodrama based on Harold Robbins' roman a clef about the Cheryl Crane-Johnny Stompanato murder case, with Joey, who was born the same year as Cheryl, playing the daughter of the Lana Turner character (Susan Hayward). A number of critics said that the filmmakers showed at least some good taste by not having Lana herself play the part. Finally, Blood was one of three 1965 horror films directed by TV's William Conrad. Joey's leading man was 60's heartthrob Troy Donahue, but the movie was indifferently received by the public.

By the 1970s, Joey's career was slowing down, but she was still popular enough in July of 1975 to headline a four-week CBS summer replacement series. Joey and Dad was a musical variety hour in the final days of that genre. "Dad", of course, was Ray Heatherton and, in a nostalgic moment, he sang his old Merry Mailman theme song.

In subsequent years, Joey performed in Las Vegas and acted in a few scattered TV shows and films, including 1972's Bluebeard, with Richard Burton in the title role, in which she appeared topless, and a starring role as Xaviera Hollander in 1977's post-Watergate-inspired The Happy Hooker Goes to Washington, but clearly her time had passed.

She also pitched RC Cola and Serta mattresses in TV commercials.

Psychological problems, as well as a well-publicized bout with drug addiction, derailed her career in the 1970s, and in 1971 her then-husband Lance Rentzel, a receiver for the NFL Dallas Cowboys, was arrested for indecent exposure in front of a young girl.

Her most recent acting role was in the John Waters film Cry-Baby in 1990.

In the 1970s and 80s, Heatherton was famously parodied in the SCTV comedy series by a recurring character, Lola Heatherton, portrayed by Catherine O'Hara.

Sadly, this glowing young girl developed a drug habit and has displayed bizarre behavior the last several times she was seen in public. In one incident, she was at P. J. Clarke's, the famous bar/restaurant, talking endlessly, and leaving without paying her tab. Dabney Coleman paid for her.

Also at her father's Funeral Mass at St. Agnes' Cathedral in her hometown of Rockville Centre, Long Island, New York, she behaved extremely erratically and was almost escorted out of the church by her rather unsympathetic family.