The actress announced plans to split from Boxleitner in March, effectively ending their 16-year marriage, though she insisted that the pair plan to remain friends.
Gilbert filed for divorce in Los Angeles Superior Court on Monday, citing irreconcilable differences as the reason behind the breakup, reports People.
She is seeking joint custody of their 15-year-old son Michael and has requested not to pay spousal support to Boxleitner.
Gilbert also helped to raise Boxleitner's two sons from a previous marriage, 31-year-old Sam and 26-year-old Lee.
Melissa's sister and The Talk co-host Sarah Gilbert announced her split from partner Allison Adler earlier this week after ten years together.