Jennifer Connelly grew up in Brooklyn Heights, just across the Brooklyn Bridge from Manhattan, except for the four years her family spent in Woodstock, New York. Her father was in the garment industry, and a close friend of the family was an advertising executive. When Jennifer was 10, the friend suggested that her parents take her to a modelling audition. She began appearing in newspaper and magazine ads (such as Seventeen magazine) and soon moved on to TV commercials. A casting director saw Jennifer and introduced her to Sergio Leone, who was seeking a young girl to dance in his gangster epic "Once Upon a Time in America."

Jennifer enrolled at Yale, then transferred two years later to Stanford. Her first appearance on celluloid (uncredited) was on a British TV series called "Tales Of The Unexpected". Her first movie appearance was in "Once Upon a Time in America" (1984). In an interview to Entertainment Weekly, Jennifer said she owed that role to the fact that her nose matched co-star Elizabeth McGovern's. Jennifer has also appeared in a rock video: "I Drove All Night", a Roy Orbison Song, co-starring Jason Priestly. There is a rumor that she appeared briefly in a Duran Duran video. She also appeared in a Miller Beer commercial. During the mid-eighties Jennifer released a single called "Monologue Of Love" in Japan, in which she sings in Japanese a charming little song with a semi classical instruments arrangement.

Jennifer is trained in classical theatre and improvisation, having studied with the late drama coach Roy London and with Howard Fine and Harold Guskin. She did TV commercials in Japan (see above). At one point she was "engaged" in an unconventional sense (i.e. no real plans to marry), to Bill Campbell, her co-star in "The Rocketeer". They were together on and off for about 5 years. Jennifer currently lives in New York. She's five feet eight (about 1.72 m), speaks fluent Italian, French and semi-fluent Japanese. She was also a member of Gold's Gym in Venice Beach for a year or two, but is no longer active. She enjoys physical activities such as swimming, gymnastics, bike riding, and roller skating. She is an outdoors person - into camping, hiking and walking.

Jennifer is interested in Quantum Physics and philosophy. She is fairly level headed and grounded as a person, and is not overly seduced by the Hollywood fantasy. She likes horses. With music she likes Pearl Jam, SoundGarden, Jesus Jones, and 'whatever sounds nice on the radio'. Occasionally Jennifer wears a small picture of the Dalai Lama on a necklace. Her favorite colors are cobalt blue, hunter green, and "a very pale green/gray - sort of like the color of the sea". She likes to draw.