*Tyrese Gibson finds himself being fitted for a new suit. A new lawsuit, that is.

The actor/singer is being sued for more than $83,000 by a woman who says he ruined her life after she wrote a book about his mom. However, Gibson says the author is the one who’s guilty of taking advantage of his mother.

The story goes that Cynthia Banks befriended Tyrese’s mother Priscilla a few years back and agreed to write a book about Priscilla’s 27-year struggle with alcoholism. Banks says the Gibson children cooperated with her on the book … except Tyrese, who publicly trashed the author and ruined her reputation.

Here’s what TMZ is reporting:

Banks filed a lawsuit against him in Texas, where she lived … but when he failed to respond to the suit, a judge awarded her $75K.

Banks says Tyrese never paid — so now she’s coming after him in California. She’s asking an L.A. judge to order him to fork over the money, which has ballooned to $83K due to interest charges.

Tyrese says he had no idea Banks had filed a lawsuit against him, but claims she “bamboozled” his mother at a low point in her life. He told us, “I did what I had to do to protect my mother from this woman who took advantage of her while she was in rehab.”

Gibson also added that his mother has been sober for 7 years, and the whole family is standing together “to make sure this goes away.”