Born in Los Angeles, California where her family still resides, to actor Michael Eugene Osment and Theresa Osment née Seifert a teacher. Osment has never been a stranger to the world of entertainment and acting. Her father, Eugene Osment, is an actor of various films, and her older brother is famous former Academy Award-nominated child-star Haley Joel Osment.

Emily made her acting debut in the 1999 film The Secret Life of Girls. A story where girls share their feelings of friendship for another but soon to involve more than just friendship. The same year she co-starred alongside Glenn Close in a Hallmark Classic, Sarah, Plain and Tall: Winter’s End, a role that would lead to a nomination for a “Best Young Actor” award. Since then, she has gone on to do a number of roles, including Gerti Giggles in the Spy Kids trilogy. She also made appearances on television shows such as Touched by an Angel, Friends, and 3rd Rock From the Sun. She is currently working on the Disney Channel series, Hannah Montana. The series premiere scored record ratings for Disney Channel: 5.4 million viewers, a response “beyond our wildest expectations,” according to the president of Disney Channel Entertainment.

While playing the role of Lilly Truscott. In 2006 Emily was also invited to participate in the first Disney Channel Games and was on the green team. In 2007 she was again asked to participate and has been put on the yellow team, the new team in this year’s games. Osment sang some vocals in Billy Ray Cyrus’s song You’ve Got A Friend from his 2007 album, Home At Last. Osment is also going to star as a gothic girl in “The Haunting Hour Volume One: Don’t Think About It” (co-starring Hannah Montana’s co-star Cody Linley) , Osment also recorded a single “I Don’t Think About It,” for the “The Haunting Hour Volume One: Don’t Think About It” Soundtrack in 2007.

On June 22, 2006, a performance of a Hannah Montana concert (featuring Cyrus as Hannah Montana) at Disney’s Typhoon Lagoon in Walt Disney World in Orlando, Florida was recorded for the Disney Channel. Hannah Montana spent the rest of 2006 opening for The Cheetah Girls on 20 dates of their 39-city tour. there was also a Disney Channel Hannah Montana promotion, “Hannah Montana’s Backstage Secrets”, in which Miley Cyrus portrays Hannah Montana in a fictional interview set in the show’s canon.

Osment is good friends with fellow Hannah Montana co-stars Miley Cyrus and Mitchel Musso, often texting and conference calling each other during busy days. Miley Cyrus also taught Emily Osment how to play the guitar and Osment taught Cyrus how to knit.

In December 2006, Disney announced plans to release Hannah Montana products including clothing apparel, stationery and dolls. Play Along Toys will be releasing the Hannah and Miley dolls and Lily/Lola dolls. Hannah Montana is signed for at least one more season according to Disney Channel. Filming for the second season started in December. The new season started in April, 2007, in which she is in high school.

Miley Cyrus has stated that they are working on ideas for a Hannah Montana movie. The feature-length film is to be produced by Miley Cyrus’s both on and off-screen dad, Billy Ray Cyrus.

Disney released a Hannah Montana clothing collection in late summer. Osment helped to design some of the pieces from the collection. “It’s not a costume. A tween girl isn’t doing dress-up, they want to look like they could be Hannah Montana’s friend. This is a fashion line”.