Chuck Liddell-- I Threw Down $2.6 Million ... To Live Like a Champ -

Legendary MMA fighter Chuck Liddell just laid down $2.6 Million of hard fought dough for a sick house in Cali ... prepping to spend his retirement days like a champ.

The Hidden Hills estate -- just north of Calabasas -- is a 5-bdrm, 5-bath, 5,923 sq. ft bad-ass mansion mere miles from the likes of Kim Kardashian and Justin Bieber.

The cool crib comes complete with a huge pool, spa, maid’s quarters, library, vaulted ceilings and full on basketball court so the iceman can practice his dunking skills alllll day long.

Icing on the cake -- the community is gate access only for tight security ... but we’re sure the UFC champ could take down a few robbers if he had to.

Check out the pics to see more.