Kim Kardashian/Kris Humphries Negotiating Prenup

Kim Kardashian and her fiancé Kris Humphries are hedging their bets -- they're hammering out a prenup before they tie the knot ... TMZ has learned.

Sources close to the couple tell us … both Kim and her NBA star hubby-to-be are telling friends, “It’s the smart thing to do." And, by the way, they're right.

We’re told the move isn’t one-sided. Both Kim and Kris have tons of loot. Kim is worth a reported $35 mil.

As for Kris ... he's not only making $3.2 mil a year with the Nets, his family also owns a couple of burger joints in Minnesota. Kris' net worth is estimated at $8 million.