Fille de Ronald et Mary Agron, elle grandit à Burlingame, Californie, dans la banlieue de San Francisco.Elle voyage toutefois beaucoup durant son enfance, et grandit principalement à San Antonio, au Texas ainsi qu'à San Francisco, en Californie. Son père, Ronald Agron, étant manager pour les hôtels Hyatt, Dianna, sa mère et son frère le suivent pour ses besoins professionnels.Elle commence la danse très jeune, dès ses trois ans, en faisant principalement de la danse jazz et classique puis, plus tard un peu de hip hop, c'est pourquoi, adolescente, elle donne des cours de danse.Elle a toujours voulu faire partie du monde du spectacle, c'est ainsi que dès qu'elle quitte le lycée, elle décide de se lancer dans une carrière d'actrice, en partant à Los Angeles.
"She was so wonderful to basically give me her home to myself and my family," Michele said. "It's certainly been a pretty rough year," Michele admitted to host Ellen De Generes."But I've been surrounded by such great people, such great family." PHOTOS: Lea Michele and Cory Monteith's romance Monteith died at the age of 31 after overdosing on heroin and alcohol.Whatever you want to do, we'll do.' I said, ' I have to go back to work. "There's this grief [that] goes with you everyday whatever you're doing. So I'd rather, for me, be at work with the people who I love that are going through [it.] It obviously has it's own triggers, but at the end of the day I feel so safe there.And like I said, they're my family." Michele and De Generes also reminisced about Monteith's famous December 2012 interview on , where he confirmed he and Michele were dating.There's this is grief goes with you everyday [with] whatever you're doing—when there are great moments, when there are hard moments—so I'd rather be at work with the people who I love that are going through it.""It obviously has it's own triggers, but at the end of the day, I feel so safe there," she continued."And like I said, they're my family."The passage of time has made Monteith's death somewhat easier on Michele, though the Broadway vet is still in mourning.But to have that time at [Hudson's] home to just really be in private with this for a moment -- before getting back to work and before going home -- I'm just so thankful to her." But Michele, whose debut solo album . they're my family." PHOTOS: Glee's best guest stars The actress did face some scrutiny from fans for returning to work too soon, but said that was the best way for her to cope."[Glee co-creator] Ryan Murphy, who is so amazing, he came to Kate's house and he said, ' What do you want to do? "What people also don't understand is that going to work is no harder than being at home and being in the house and opening up a closet and seeing a pair of shoes," Michele explained."I really feel like I'm still trying to figure out all of this.It's been only a few months, but my mom has experienced a lot of loss in her life and she told me at one point, there is an empowerment that comes with grief—at some point you find it.