Rob Kardashian: Masking the Real Rob

Rob Kardashian posted a mysterious pic that has a lot of people wondering if this is Rob 2.0 ... it's not.

Rob put the pic up on Instagram early Wednesday, showing him substantially shielded with a bandana.

Turns out he posted the same pic on his 27th birthday back in 2014 and then took it down.

As we reported, Rob's family is worried sick he's not taking his diabetes diagnosis seriously and isn't taking steps to get better.