Dewan cited irreconcilable differences as the reason for the split, TMZ reported. She also requested spousal support and joint legal and physical custody of their 5-year-old daughter, Everly.
Tatum agreed to joint custody of Everly, but is trying to block the court's ability to award Dewan spousal support.
Dewan and Tatum announced their separation in April after nearly nine years of marriage.
Earlier this month, media reports said Tatum is dating singer Jessie J.