Buzz Aldrin -- I'm Just Going To Say It ... TANG SUCKS!

Buzz Aldrin says he HATES TANG ... and due to the fact he's been married to 3 women, we're guessing he meant the drink.

Of course, Tang (the drink) shot to fame as the stuff the astronauts like John Glenn sipped on during space missions back in the day.

Tang is to astronauts ... like crack is to whores -- or so we thought! Because at the taping for Spike TV's Guys Choice Awards this weekend -- Buzz shockingly proclaimed, "TANG SUCKS."

And why the revelation?

Buzz was presenting an award to Felix Baumgartner (the Austrian skydiver who jumped from space last year) ... when he began talking about how jealous he was of Baumgartner's Red Bull sponsorship.

Buzz proceeded to gripe about how no corporate sponsor ever paid HIM to go to space -- not even Tang -- and that's why he didn't feel bad trashing the drink.

Wonder how he feels about Astronaut ice cream ...?