In the papers, Aguilera cited "irreconcilable differences" as the reason for the split.
She also asked for joint physical and legal custody of their son, Max, TMZ reports.
Aguilera, 29, and Bratman, 33, wed in California's Napa Valley in November 2005, after becoming engaged in Carmel, Calif., in February of that year. Their only child, Max, was born in January 2008.
Earlier this week, Aguilera told PEOPLE: "Although Jordan and I are separated, our commitment to our son Max remains as strong as ever."