Allen Hurns is unloading his Jacksonville pad after the Jaguars kicked him to the curb this offseason ... putting his Florida creekside mansion up for sale for $1.3 MILLION ... TMZ Sports has learned.

The new Dallas Cowboys wideout bought the place back in August 2016 a few weeks after inking a 4-year, $40 million deal with the Jags ... but, Jacksonville cut him this past March -- so his loss can now be your gain!

The place is fancy ... with Jim Pittman of Pittman Real Estate Team tellin' us it's got five bedrooms, four bathrooms (plus two half baths), 5,805 square feet -- and a huge covered pool in the backyard.

It's also got its own dock leading to the creek in the yard ... but no word yet if the two jet skis parked there come with the crib.

Don't feel bad for Hurns for having to cut ties with the spot ... he signed a 2-year, $12 million deal with the Cowboys ... AND he could theoretically make $200k on the mansion if he gets his asking price.

Some guys have all the luck.