Jessica was born in San Francisco , California on April 18, 1989.
She auditioned at the SM Casting System and joined the company in 2000. She was trained at SM Entertainment for 7 years and 6 months. Jessica is a 2007 graduate of Korea Kent Foreign School As she was born and raised in the United States, Jessica can speak Korean and English fluently.
Her younger sister Krystal is a member and one of the lead vocalists of girl group f(x)
In addition to her group activities, Jessica released two singles alongside with Seohyun and Tiffany Oppa Nappa and "Mabinogi (It's Fantastic!)". In May 2008, she with fellow members Tiffany and YoonA and DBSK had a commercial for an upcoming CF for Haptic Motion.
In addition, she had various duets — one with SHINee member, Onew, called "One Year Later", and one with Park-Myung Su "Naengmyeon".
She also sang the "Seoul Song" with Super's Leeteuk, Kyuhyun, Siwon, Sungmin and Donghae and fellow group members Sooyoung , Seohyun , Taeyeon And Sunny .Furthermore, she participated in music videos for Kim Jo-han and Super Junior-M
She was also featured in
Super Junior-M's Music Video ''Super Girl''
Jessica made her musical debut in the Korean production of Legally Blonde : The Musicall alongside Honey Lee and Kim Ji-woo; the production opened on November 14, 2009.
It was revealed on March 7, 2010 that she will play a cameo role on SBS Oh My Lady! starring Choi Siwon and Chae Rim with her colleagues Sooyounng And Hyoyeon
From May 10, 2010 Jessica was a fixed member of the show "Happy Birthday" for one month. She was withdrawing from the show on June 7, 2010 because of SNSDs overseas activities.