Jennifer Welles was born in northern New Jersey, the youngest of two daughters to a German aircraft designer and his wife who had fled Nazi Germany. When Welles was just nine years old, her father left the family for another woman, and she never saw him again. Her mother, a very protective and hardworking individual, raised Welles alone, often working long hours in a factory and leaving Welles home alone. Welles' older sister had married at a young age and moved away, leaving Welles to fend for herself.
Welles quit high school and pursued a career in dance, performing in dinner theater and traveling troupes during the early 1950s. She soon moved to Las Vegas, where she danced in opening acts for famous comedians such as Jack Benny and the comedy duo of Dean Martin and Jerry Lewis. Welles returned to the east coast and studied drama under the renowned Sanford Meisner. She continued to dance in stage productions and eventually married professional musician Manny Duran.
By the end of the 1960s, Welles had become involved in acting in low-budget softcore exploitation films in New York City. In the mid-1970s, at the age of forty, Welles began making explicit hardcore adult films, enjoying a large following. Although she claimed her husband had no problem with her career, they soon divorced, and she married a wealthy businessman named Phillip, who was about ten years younger.
Phillip lavished Welles with a large Tuxedo Park home and money to spend, and she left the adult film industry by the end of the decade. The couple moved to Houston, where Welles became involved in raising horses. However, her husband began an affair with another woman, and the marriage was soon over. Welles is now in her seventies, living alone in a rural location in America, with a few cats, dogs, and two horses. She attends church regularly and has no regrets about her film career.