Miley Cyrus will never forget her deceased dog ... because it's now emblazoned on her rib cage.
Miley inked the memoriam Saturday at a house party in Los Angeles. For some reason ... her good buddy Wayne Coyne from The Flaming Lips and another friend tatted the same design in honor of Floyd -- an Alaskan Klee Kai that died when he was only 2.
Floyd's death ... along with a bad reaction to antibiotics and hard partying ... led to Miley's meltdown earlier this year.
It looks like Floyd's mug is the centerpiece of the tat with the words, "with a little help from my fwends."
We'll always remember Floyd ... because we have to now.