USC didn’t just take Lane Kiffin‘s dignity, the university might also be in a position to take his house … TMZ has learned.

We broke the story … after Lane accepted the head coaching job at the University of Southern California in 2010, the school agreed to loan him $500k to use toward the purchase of a $5.5 million mansion in Manhattan Beach, CA.

But there was a catch … under the terms of the deal, if Lane got fired or quit during the life of the loan, USC could demand the $500k back, plus interest STAT … and if he didn’t pay up, SC could foreclose.