Beyonce's Pregnant Belly Covered in Henna Tattoos at Second Baby Shower

Beyonce is just about ready to pop -- and it REALLY showed at her 2nd baby shower this weekend ... mostly 'cause of her belly tattoos.

Bey hosted a "Carter Push Party" Saturday and invited her mom, Tina, and a few her famous gal pals -- including her Destiny's Child crew Michelle Williams and Kelly Rowland ... plus Lala Anthony AND fellow expecting mom Serena Williams.

But the highlight was obviously Queen Bey, who was walking around in some kind of tribal outfit with her very preggo belly fully exposed ... and covered in henna tattoos. Reminds us of when she first announced the twins.

It seems like any day now, but Bey's dad Mathew Knowles said on "TMZ Live" Friday she was more than 2 weeks away.