Paris Hilton -- She's Got a Baby!!

Paris Hilton has a new fashion accessory ... DISPOSABLE BABY!!!

P cradled the infant like a pro at LAX -- just a few minutes ago -- when, for some reason, a very brave parent handed over the kid.

The baby looks to be no more than a few weeks old -- so besides birth, this has to be the most harrowing moment of his life ... though Paris actually shows a bit of maternal instinct here. For a whole 30 seconds.