The "Braveheart" director and his former musician girlfriend Oksana Grigorieva agreed to a settlement detailed in a Los Angeles Superior Court hearing on Wednesday following a more than year-long war of words.
Judge Peter Lichtman banned both Gibson and Grigorieva from writing books about their relationship, which unraveled in early 2010 amid accusations of violence and extortion.
"I would like to thank your honor for bringing this matter to a reasonable conclusion," Gibson told Lichtman at Wednesday's hearing.
Grigorieva, who had been seeking millions of dollars from the Oscar-winning actor, thanked Lichtman for "the tremendous help to resolve this situation."
The acrimony between the couple became public a year ago when taped phone calls were leaked online in which Gibson was heard ranting, cursing and insulting Grigorieva.
The leak appeared to have been aimed at putting pressure on the actor to increase an initial settlement offer to Grigorieva that was reported to be around $15 million. Los Angeles prosecutors later decided against charging Grigorieva with extortion.
In March, Gibson admitted slapping Grigorieva during an argument and was sentenced to three years probation.
The widely-heard tapes further tarnished a reputation damaged by Gibson's 2006 anti-Semitic tirade following a drunk driving arrest in Malibu.
His manager quit, he lost a cameo role in "The Hangover: Part Two" because other people refused to work with him, and the release of his movie "The Beaver" was delayed and ultimately flopped at box offices in May.
Gibson, who was once estimated to be worth $900 million after a string of hit movies like "Lethal Weapon" and "The passion of the Christ", reached a private settlement with his wife Robyn in June that wrapped up their divorce after 28 years of marriage.