Fruity beers are pretty much all disgusting to me. As far as regular flavored beers, Tsingtao was so gross I almost vomited. Could have been a bad batch, or skunked, but I haven’t tried it since.
Nah, no malt liquors. They almost all taste bad. The only one I could ever stand was Steel Reserve from a can. But it’s still pretty bad.
Back in the 80s I drank some Carling Black Label. Horrible, horrible stuff!
More recently, Tequiza. Ghastly!
China has a regional beer called “Shancheng.” It’s weak and undistinguished, but relatively drinkable. At twenty cents a (large) bottle, it was the go to beer in the city where I lived.
Until one day, a batch went bad. Something went wrong at the factory, and suddenly every beer in town was just gross tasting. Everyone quickly switched to spirits or another brew. But the vendors, loathe to lose money, held on to the bad beer. So for about a month, it was a game of chicken. Now and then someone would order a Shancheng and learn that yup, the bad batch hadn’t run out.
Time passed, and eventually someone, somehow, managed to drink through the bad batch, and all was well in the world again.
Ortlieb’s (“Joe’s Beer”). Disgusting. 1980-1983.
I actually kinda like Steel Reserve in a bottle.
I also grew up on PBR. And Schaefer was the worst beer I ever drank.
Tuborg Gold, in the late 70s.
Hamms. When it was owned by the Olympia Brewing Co… Tasted green and skunky at the same time.
the absolute worst, however, was some crap the Navy used to give to enlisted personnel in the Phillippines. Tasted like formaldehyde. In fact I believe it actually was formaldehyde.
Wow, what an amazing coincidence. I had the worst beer I have ever tasted just yesterday. I only took one swig and can’t remember the brand, but it was a sorghum beer (drinkable for the gluten-free). It was like a bad dream of beer. It looked like urine, had a sickly sweetish flat taste with a faint representation of decay, and and a despicable aftertaste of, well, sorghum.
I live in China. Supposedly, “imported” beer sold in China is actually brewed here, so I should be insulated from the “Beer tastes worse the further it’s shipped” maxim.
That said, I had a Boddington’s last night that tasted like an ash tray.
Friend of mine used to bring Labatts 50 to every party. He could guarantee that no one else would take it out of the cooler.
I am not a beer drinker, bit people keep trying to get me to like it. I have had clove-tasting ones, cinnamon-tasting ones, raspberry-wheat, darks, reds, Lagers, ales, stout and various others. I don’t really like the stuff, but on a hot day when it’s icy-cold, it’s okay.
I will say I have ruined some for others since apparently I can taste notes they can’t, until I tell them about it. 
Just out of curiosity, was it on-tap, bottled, or canned? I had an on-tap pint of Boddington’s last week and it tasted okay.
Incidentally, reading this thread is giving me an odd feeling of déjà vu.
The Heineken I’ve had in the Netherlands actually isn’t bad, but I agree with you about what ends up here in the US. I’ve always been a bit skeptical about claims about how so very different beers are in their home countries, but Heineken and, even more so, Pilsener Urquell proved to me that there is merit to this claim.
My normal answer to this is Busch Light, but I had this one-off anniversary beer called Baltika 10 Jubileum in Moscow that was flavored with basil and almonds. It was terrible and tasted not unlike putting a teaspoon of pesto into a beer.
Tesco Everyday Value Bitter. Four cans for a pound. Cheaper than homebrew, and twice as vile.
The worst I’ve had I think would be Arrogant Bastard ale. I know it’s supposed to be good, but I didn’t finish half before I threw it away. I believe it even says on the bottles “you probably won’t like this” and they were right.
Concord Grape Ale.
In all my beer drinking experience, this is the only commercially available beer I could not finish.
And for those of you who said Olympia, I’ll be outside if you want to discuss it further.
2.1% alcohol?
I was a can collector way back when so I’ve probably drank more rank beers than anyone in this thread. Two of the worst were Griesedieck (which we pronounced, of course, “greasy dick”) and Stortz.
Early 70s. Jax Beer. New Orleans brew.
Untreated swamp water.