Former Beverly Hills, 90210 star Brian Austin Green is suing the mother of his son for cash he alleges she owes him.

The actor, who is now married to Megan Fox, claims Vanessa Marcil-Giovanazzo owes him $200,000 she borrowed from him.

In the lawsuit, filed in Los Angeles and obtained by TMZ.com, Green claims his former partner, who also appeared on Beverly Hills, 90210, promised to pay him back, but when the actor asked for his cash back in November, she refused.

He is demanding all the cash he loaned her, plus unspecified damages.